annual report 2009 – 2010 - raman research institute · the retirement of sir c v raman from iisc...
TRANSCRIPT
Annual Report2009 – 2010
Raman Research InstituteBangalore
Scientific research is firstand foremost an expression
of the resurgence of thehuman spirit in its search for
self-expression. Itrepresents the response of the
mind of man to themarvellous and ever-
changing panorama of
f fd foremost an expressioof the resurgence of theman spirit in its search f
self-expression. Itresents the response of thmind of man to the
marvellous and ever-
S cientific research is first and
foremost an expression of the resurgence of the
human spirit in its search for self-expression.
It represents the response of the mind of man to
the marvellous and ever-changing panorama of
Nature.
– C V Raman
IntrIntrIntrIntrIntroductionoductionoductionoductionoduction From the Director ......................................... 6
About the InstituteAbout the InstituteAbout the InstituteAbout the InstituteAbout the Institute History .......................................................... 7
RRI at a Glance .............................................. 11
ArArArArAreas of Reas of Reas of Reas of Reas of Researesearesearesearesearchchchchch Astronomy and Astrophysics
Overview ................................................ 14
Ongoing Research .................................. 20
Light and Matter Physics
Overview ................................................ 30
Ongoing Research .................................. 34
Soft Condensed Matter
Overview ................................................ 40
Ongoing Research .................................. 45
Theoretical Physics
Overview ................................................ 56
Ongoing Research .................................. 59
FFFFFacilitiesacilitiesacilitiesacilitiesacilities ..................................................................... 65
AAAAAcademic Prcademic Prcademic Prcademic Prcademic Programsogramsogramsogramsograms ..................................................................... 70
PPPPPeople at RRIeople at RRIeople at RRIeople at RRIeople at RRI ..................................................................... 72
PublicationsPublicationsPublicationsPublicationsPublications ..................................................................... 84
Other AOther AOther AOther AOther Activitiesctivitiesctivitiesctivitiesctivities ..................................................................... 85
AppendicesAppendicesAppendicesAppendicesAppendices ..................................................................... 89
Statement of AStatement of AStatement of AStatement of AStatement of Accountsccountsccountsccountsccounts .....................................................................133
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contents
The Annual report of the Raman Research Institute for the year
2009-10 is a summary of the research and academic activities of
the Institute during the year.
The Annual report presents synopses of the ongoing knowledge creation
activities in the different research groups, many of which have outcomes
in the form of publications in refereed scientific journals. The Institute
considers the transmission of knowledge an important activity; this
includes the guidance of students for the conferment of PhD degrees as
part of the PhD programme of the Institute, as well as the active Visiting
Students Programme
under which a number of
students from all over the
country visit the Institute
for stays ranging from a few weeks to several months and participate in
the many research activities of the Institute. Communications of the
ongoing research and also a sharing of knowledge of current research –
in professional talks given by members of the Institute in conferences
and in external institutions as well as Journal Review talks at the Institute
– is another aspect of our knowledge diffusion. A cultural function of a
premier research institute is the upholding and promotion of academic
traditions and this includes the conduct of specialized seminars on
technical topics targeted at specialized audiences as well as colloquia in a
wider range of topics that are delivered in a style that strives to make
current advances intelligible to a wider community. Additionally,
outreach activities include writings intended for a lay and discerning
audience as well as the delivery of motivational talks at educational
institutions.
Included in this report are lists of publications in refereed journals,
conference proceedings as well as in monographs, books and in popular
periodicals, PhD degrees awarded during the period 01 April 2009 to 31
March 2010, as well as seminars and review meetings focussed on
current research, which were held at the Institute. The report also lists
the scientists who have visited the Institute from within India and from
overseas during the period.
Bangalore Ravi Subrahmanyan
August 31, 2010 Director
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from the Director
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Before jumping to the next pages in
search of the current exciting research
activities conducted at the Institute, take
a few moments to read about its history.
In between the collection of historical
facts you’ll discover a story about the
power of basic human curiosity – the
invisible foundation on which the Raman
Research Institute was built and
managed by its founder Sir C V Raman
and subsequently by his successors.
history
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In 1934, while still the director of the IndianInstitute of Science (IISc), Raman startedthe Indian Academy of Sciences and
attracted most of the best young scientists ofthat time, who published their work in worldrenowned journals of physics and chemistry.The same year the Maharajah of Mysore giftedto the Academy 11 acres of land in the northside of Bangalore. Few years later, Ramanproposed that an independent researchinstitute is built on that premises and anagreement with the Academy was signed.Raman embarked on a number of longjourneys throughout the country to raise fundsfor the new institute. In 1943, the collectedsum, along with his personal savings, wasallotted for the construction of the firstbuilding. Its initial completion coincided withthe retirement of Sir C V Raman from IISc in1948 and in the beginning of 1949 he shiftedall his activities there. The new center wasnamed after its founder - Raman ResearchInstitute.
From the very first moment of its foundationRaman undertook the management of his newinstitute with immense vigor and enthusiasm.He not only designed the main building withthe help of an architect, but also took greatinterest in the arrangement of the wholepremises. He planted trees, decorative bushesand flowers turning the barren land aroundinto a beautiful garden. A walk in that garden
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was an indispensable part of his daily life. Theinitial staff in the new institute consisted offour people including Raman himself. The lackof electricity during the first two years didn’taffect Raman’s thirst for knowledge andunderstanding the wonders of Nature. Greatscientific work was carried out during theseyears using a few lenses and a manuallyoperated heliostat. In order to support his staffand expand the scientific activities at RRI,Raman who was unwilling to take money fromthe Government, started a couple of chemicalfactories along with one of his formerstudents. He used the profit to pay his staffand equip his laboratories. In the years tocome, the institute kept expanding – soonthere was a new library, few other buildingsand a museum holding Raman’s personalcollection of gems, crystals and minerals. Untilhis death in November 1970, Raman keptworking tirelessly for the development andgrowth of the Raman Research Institute.
After his death, the Academy created a publiccharitable trust: the Raman Research InstituteTrust. The lands, buildings, deposits, securities,bank deposits, moneys, laboratories,instruments, and all other movable andimmovable properties held by the Academyfor the Raman Research Institute weretransferred to the RRI Trust. The foremostfunction of the RRI Trust was to maintain,conduct and sustain the Raman ResearchInstitute. In 1972, the institute startedreceiving funds from the Department ofScience and Technology of the Government ofIndia which, since then, has been its main
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Facing page: The RRI building during its constructionin 1949; a group photograph taken at the Institute;the Nobel Ceremony where Raman was awarded thehonour.
This page (from top): C V Raman with Heisenberg;with Dirac; and giving lectures in the Institute labsand elsewhere
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funding source. The same year, VenkatramanRadhakrishnan was invited to be the directorof RRI. A renowned scientist himself,Radhakrishnan not only fulfilled C V Raman’sdesire to build an observatory at RRI butformed a strong group in Astronomy andAstrophysics whose research work today isregarded highly worldwide. Until the mid 90s,the two main areas of research were LiquidCrystals and Astronomy and Astrophysics. Theconstant growth of the Institute and theexpansion of the research interests of itsmembers led to the establishment of two newgroups – Theoretical Physics and Light andMatter Physics. The Liquid Crystal group wasrenamed to Soft Condensed Matter whichconveys more accurately the diverse researchactivities of its members.
Today, RRI research faculty, scientific staff andstudents conduct active research in the abovementioned four scientific fields inspired by theexample of the founder – Sir C V Raman.
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On this page: C V Raman engages with visitors,students and children in the Institute during its earlydays.
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RRI at a glance
Mission
RRI is engaged in fundamental researchin the areas of Astronomy, Astrophysics,Light and Matter physics, Soft CondensedMatter and Theoretical Physics as a partof the global endeavor of humanity toincrease our knowledge and understand-ing of the world.
Director
The current director of the RamanResearch Institute is Ravi Subrahmanyan.
Organization
RRI is an autonomous research institute.The supreme body of RRI is the RRI Trust.The director is the chief executive andacademic officer. The Governing Councilis the executive body responsible for theadministration and management of theRaman Research Institute. The financialmatters are conducted by the FinanceCommittee at RRI.
Location
RRI is located on a 22 acre plot in thenorth side of Bangalore City, the IT capitalof India. It offers a quiet recluse from thebustling megapolis and a natural environ-ment which is highly conducive to cre-ative scientific work.
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Facilities
1. LABORATORIES
A&AA&AA&AA&AA&ARadio Astronomy Labs:
a. Digital Signal Processing (DSP) Labb. RF and mm Wave Labc. X-ray Astronomy Lab
LAMPLAMPLAMPLAMPLAMPQuantum Optics LabLaser Cooling and Light Propagation LabQuantum Interactions LabNon Linear Optics LabLaser-induced Plasma Lab
SCMSCMSCMSCMSCMChemistry LabPhysical Measurements LabLiquid Crystal Display LabRheology and Light Scattering LabX-Ray Diffraction LabBiophysics LabElectrochemistry and Surface Science Lab
MECHANICMECHANICMECHANICMECHANICMECHANICAL ENGINEERINGAL ENGINEERINGAL ENGINEERINGAL ENGINEERINGAL ENGINEERINGMechanical WorkshopGlass Blowing Facility
2. LIBRARY
3. COMPUTER FACILITIES
4. CAMPUS
Education
RRI offers the followingacademic programs:
PhD Program
Post Doctoral FellowshipPrograms
Visiting Student Program
Funding
RRI is funded by the De-partment of Science andtechnology, Government ofIndia.
Research Areas
Astronomy and Astrophysics
Light and Matter Physics
Soft Condensed Matter
Theoretical Physics
Research, Scientific/Technical,Administrative Staff and PhD Students
Research faculty: 39
Scientific/Technical: 48
Administrative: 23
PhD Students: 57
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Astronomyand
Astrophysics
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Astronomyand
Astrophysics
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Sir C V Raman could not fulfill his strong desireto build an astronomical observatory at theRaman Research Institute (RRI) within hislifetime. It was left to Radhakrishnan to dothat. During the years Radhakrishnan served asthe director of RRI, he worked tirelessly toestablish a strong group of scientists andengineers in astronomy, astrophysics andastronomical instrumentation. Today, theAstronomy and Astrophysics (A&A) group atRRI is a collection of highly motivated, curiousand open minded researchers who venture toexplore the vastness of the Universe from itscreation to its present state.
Currently, the A&A group consists of 27members whose individual interests cover theareas of theoretical astrophysics, observationalastronomy, astronomical instrumentation andsignal processing. These are the four pillars onwhich the science of astronomy rests.Astrophysics concentrates on the developmentof analytical models and computationalnumerical simulations that try to describe thedynamics, physical properties and underlyingphenomena of celestial objects (stars, planets,galaxies, interstellar medium, etc.) as well asanswer fundamental questions about theformation and evolution of the Universe.
Observational astronomers “observe” theUniverse with numerous telescopes builtaround the world covering large range of theelectromagnetic spectrum – from lowfrequency radio waves to extremely energeticgamma rays. These observations are used totest existing theoretical models and give “foodfor thought” back to the astrophysicscommunity. It is in the process of suchinteractions that the collective knowledgeabout our Universe accumulates.
Our own eyes deliver to us a beautiful butlimited image of the outer space and eversince Galileo built his first telescope in 1609,these instruments have become our new“better” eyes for space observations. Theinstrumentation engineers at RRI constructtelescopes to study celestial objects ino
verv
iew
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different frequency bands, allowingastronomers to peek into the most distantcorners of the universe back towards the timeof its creation.
While creating the necessary academicenvironment for its group members toconduct research in their field of specialization,RRI strongly encourages collaborationsthrough various activities like coffee meetings,seminars, invited talks, colloquia, etc. Thisoften leads to joint pursuit of problems intheory and observations at institutional,national and international level. The stronginteractions with the members of the RadioAstronomy Lab result in the development of avariety of astronomical instruments. Theseinclude stand-alone telescopes as well asspecial-purpose receivers that may add valueto existing telescope facilities, and allow newand specific astronomy research. Having strongexpertise and experience in the field of low-frequency astronomical instrumentation, RRIhas expanded its activities to includeinstrumentation in mm wave and X-rayfrequency bands.
The following pages summarize the majorareas of research for the Astronomy andAstrophysics group. Each member’s individualwork during the last year is provided in thenext section, giving the reader more detailedand technical description of their respectiveresearch activities.
ASTROPHYSICS
Development of cosmological models –cosmology as a branch of astronomy isconcerned with developing and testingphysical models that try to explain theformation and evolution of the universe.Researchers at RRI are working on developingcosmological models describing the radiationfrom the epoch of reionization. The Epoch ofReionization (EOR) refers to the period in theearly history of the universe during which theemergence of the first luminous sources (stars,galaxies, etc) ionized the predominantlyneutral intergalactic medium. Such models willprovide insight about the processes ofstructure formation in the universe and answerquestions as to whether such radiation can bedetected with the currently existingtelescopes.
Magnetohydrodynamic (MHD) Turbulence –Turbulence in electrically conducting fluids israrely observed here on Earth. However, ingalaxies, clusters of galaxies and the interstellarmedium, where matter is ionized, it is awidespread phenomenon. Researchers at RRIare actively working towards the developmentof a comprehensive theoretical formulation ofMHD turbulence.
Dynamo Theory – The astrophysics communityat RRI conducts theoretical work towardsunderstanding of the origins of large magneticfields around cosmic objects (stars, planetsand galaxies) and the processes that sustainthem. It is such magnetic fields that protectthe Earth from the solar wind of particles thatwould otherwise destroy life on our planet aswe know it today.
Gravitational dynamics – The construction ofmodels that describe the structure of theorbits of cosmic bodies around black holes isanother of RRI researchers’ goals. One of theways of studying and observing thegravitational lensing (gravitational bending oflight) predicted by Einstein, is through studyingthe orbits of stars close to massive black holes.
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X-ray emission from radio galaxies – X-rayemissions from radio galaxies have beenobserved. RRI is working on developing atheory which tries to explain the radio and X-ray properties of such galaxies.
OBSERVATIONAL ASTRONOMY
Gas clouds and winds from galaxies – RRIstudies the mechanisms of ejection of gasclouds from galaxies using observational data.
Halo and relic radio sources – Clusters ofgalaxies are the largest structures of matter inthe Universe and understanding of theirformation, structure and dynamics can bringan important insight about its evolution. Halosand relics are structures within a galaxy clusterthat emit strong radiation in the radio portionof the electromagnetic spectrum. Variousmodels exist that try to explain the origin ofthis radiation. Currently, researchers at RRIcompare observational data from GiantMetrewave Radio Telescope (GMRT) telescopewith existing models and provide feedback tothe astrophysics community.
Evolution and lifetime of AGN – Many of thegalaxies in the universe regardless of theirclassification share the same core structurecalled Active Galactic Nucleus (AGN). In thecenter of these galaxies, a massive black holecontinuously drags intergalactic gas to itsdepths and in the process forms around it adough nut–shaped disk of matter calledaccretion disk. The matter in the disk mayescape the black hole in the form of jetsspreading in opposite directions. The velocityof these particles is relativistic allowing them togenerate what is known as synchrotronradiation that reaches us and gets captured byour radio telescopes. Recently, there havebeen observations of radio galaxies with AGNsthat are slowly dying out. How many suchgalaxies stay invisible to us because of thelimitations posed by the sensitivity of today’stelescope receivers and what brings the end of
AGN are some of the questions that concernresearchers at RRI.
HI regions in the Milky Way interstellar medium– After the Big Bang some 13.7 billion yearsago hydrogen was created in great quantitiesin the Universe making it the basic buildingblock of stars. The space between the stars isfilled with neutral hydrogen at extremely lowdensities compared to the air we breath hereon Earth. The emissions from these hydrogenregions called “HI regions” carries informationabout the conditions before star formation.Researchers at RRI look at the formation andstructure of such HI regions usingobservational data from various radiotelescopes in India and abroad.
Pulsars – The detection of pulsars was one ofthe serendipitous discoveries in astronomy.Pulsars are known to be neutron stars,originating in supernovae, that spin very fastdue to conservation of angular momentumand periodically emit radio waves. Because oftheir periodic emission, pulsars are often called“the lighthouses of the Universe”. We canobserve only these pulsars which beam in thedirection of the Earth. Pulsar emissions provideinsight about their structure and distance.They are also wonderful experimental platformto test general relativity. Today millisecondpulsars are one of the most accurate clocksthat have been found in the Universe. RRIcontinues to conduct active research on
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pulsars and develop receivers that would revealfurther details about their nature.
Life cycle of Radio Galaxies - With the everincreasing sensitivity and resolution of today’sradio telescopes, intricate features andmorphologies of and within radio galaxies canbe observed. Peculiar type of galaxies calledrestarting radio galaxies have captured theinterest of researchers at RRI. It is believed thatthe activity in the nucleus of such galaxies hadstopped for some time and then started againfresh. Such a scenario would explain theobservations made and provide a useful inputto our understanding of the evolution and lifecycle of radio galaxies. Why did the nucleusdie, how long it was dead before it restarted itsactivity, what are the mechanisms thattriggered its rebirth – those are some of thequestions RRI astronomers are trying to answerin collaboration with Indian and internationalcolleagues.
Radio Galaxy Morphologies - In recent years,the interest among the astronomy communityin what is known as X-shaped radio galaxies hasgrown and members of the A&A group at RRIare active participants in this research field. InX-shaped radio galaxies the typical two lobesare accompanied by two others to form aradio galaxy whose lobes look like the letter X.Two of the lobes are active while the other twoare dead. Theories compete to explain how thetwo additional lobes are generated. Currentobservations at RRI are used to test thesetheories and deepen our understanding of X-shaped radio galaxies.
INSTRUMENTATION – DESIGNAND DEVELOPMENT
Mauritius Radio Telescope – Mauritius RadioTelescope was built in the late 90s in Bras d’Eauat the north-east side of Mauritius, incollaboration between RRI, Indian Institute ofAstrophysics and University of Mauritius. It’s aT-shaped 2x1km aperture synthesis array whichobserved the sky at 151.6 MHz in the
declination range of -70deg to -10deg. Thescientific objectives of MRT are to produceradio surveys of the southern sky, observe andstudy pulsars, solar radio emission,extragalactic radio sources, supernovaremnants and steep spectrum sources.Currently, a research group at RRI is analyzingdata from a 150 MHz survey – one of the firstextensive low radio frequency surveys of thesouthern sky.
Giant Meterwave Radio Telescope (GMRT) –GMRT is the largest low frequency telescope inthe world used by astronomers from aroundthe globe. The collaboration between TataInstitute of Fundamental Research, Mumbai(TIFR) which currently operates the telescope,and RRI has a long tradition. RRI has previouslydeveloped receivers in the 20-cm band as wellas specialized receivers for pulsar observationsthat have been installed on GMRT to improveits observational capabilities. Currently,researchers and students at RRI are developing50 MHz receivers for the GMRT. Such receivershave been installed on four of the GMRTantennas. After extensive testing, a proposalhas been submitted for the fabrication andinstallation of the receivers on all 30 antennas
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to carry out an all sky survey at 50 MHz withunprecedented sensitivity and resolution in thelow frequency regime. Low frequency surveysallow for statistical analysis of astronomicalobjects with high redshifts and also provideforeground information crucial for studies ofthe epoch of reionization (EoR).
Wideband Receivers on Green Bank Telescope –Researchers at RRI have developed a widebandmulti channel receiver for pulsar observationsthat was recently installed in the largest singledish telescope in the world – the Green BankTelescope in West Virginia, USA. The receiversallow for high time and spectral resolution of
pulsar emissions. Data from the observations iscurrently being analyzed.
Decameter Wave Radio Telescope atGauribidanur – The decameter wave radiotelescope at Gauribidanur (80 km north ofBangalore) is built and operated by RRI andIndian Institute of Astrophysics. It’s a 1.4 km(E-W wing) by 0.5 km (South wing) T-shapedarray consisting of 1000 dipole antennas.Radio emissions from the Sun’s corona andvarious radio sources at 34.5MHz have beenobserved using the telescope. RRI researchersare currently analyzing pulsar data collectedusing the E-W wing of the telescope.
Murchison Widefield Array (MWA) – MWAproject is an international effort to design andbuild novel low-frequency radio telescope toobserve signals from the epoch of reionization,measure the heliospheric plasma and conducta high sensitivity survey of the dynamic radio
sky. The MWA will consist of 8000 dual-polarization dipole antennas optimized for the80-300 MHz frequency range, arranged as 512“tiles”, each a 4x4 array of dipoles. A test bedof 32 tiles is already deployed in the radio-quite zone in Western Australia, near the townof Geraldton providing the first sets of datafrom the instrument. RRI is a full partner in thisproject along with US and Australianinstitutions. Engineers and scientists from theA&A group have designed, built and tested thedigital receivers and data processingelectronics for the MWA telescope. Currently,they are looking at data collected with the 32-tile test bed in an attempt to understand theefficacy of different observing, calibrating, anddata processing strategies for the detection ofsignals from EoR.
Ooty Radio Telescope – new broadbandreceivers that will allow for higher sensitivityand wider field of view are currently beingdesigned and constructed at RRI for the OotyRadio Telescope.
15m preloaded parabolic dish – The institute isinvolved in the development of low-cost,robust 15m parabolic dish antennas that areneeded for grand telescope projects likeSquare Kilometer Array (SKA). The project is ata stage when the mechanical aspects of thedesign are being tested on a 12 m dishdeployed at Gauribidanur.
3m submm wave telescope prototype(3mSTeP) – mm and submm wave bands are
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extremely attractive for a number of reasons.Unlike optical radiation, mm and submm wavestravel unabsorbed by the interstellar cloudsand dust. This allows us to peak inside theclouds where stars and galaxies are formed - amain driving force in the development andconstruction of telescopes at thesefrequencies. Observations would also bringvaluable information about the cosmicmicrowave background (CMB), the afterglow ofthe enigmatic gamma ray burst, star formationprocesses at high redshift, and more. However,the major problem at these frequencies is theEarth’s atmosphere which is opaque for mostof the band. That requires telescopes to bedeployed at high altitudes in order to minimizethe travel of submm waves through theatmosphere. Members of the A&A group arecurrently involved in the hardwaredevelopment of a 3m submm wave telescopewhich would serve as a prototype for thedevelopment of a 30m telescope. They havealready resolved challenges in the mechanicaldesign of the dish and the development of anenergy efficient motor system needed for theremote deployment, where power grid doesn’treach. The group is currently working on theconstruction of very broadband 8GHzspectrometers needed for the telescopereceiver system.
X-ray polarimeter – Recently, the A&A grouphas expanded its observations beyond radioand mm waves to the X-ray region of thespectrum. RRI has built a fully equipped lab forfabrication and testing of X-ray detectors andcurrently, researchers are working on thedevelopment of an X-ray polarimeter, sensitivein the energy range of 5-30 keV. Theinstrument will be launched in space incollaboration with ISRO. The PI of the projectsays: “ The X-ray astronomical research and in abroader context, high-energy astrophysicsresearch will be strongly enriched from X-raypolarisation measurements of many kinds ofastrophysical objects. In absence of any X-raypolarisation mission presently approvedanywhere in the world, the proposed
experiment will be the pathfinder of future,more sensitive experiments….Earth’satmosphere completely absorbs photons inthe X-ray and gamma-ray band. Therefore,observations of X-ray sources can be carriedout only from space platforms like balloons,rockets, or satellites. To achieve a reasonablesensitivity, the proposed experiment requiresvery long observations of bright X-ray sourcesthat are only possible from a satellite.”
ASTROSAT LAXPC- ASTROSAT is the name givento the Indian Space Research Organization(ISRO) satellite mission for multi-wavelengthastronomy, scheduled to be launched in a 650km near equatorial orbit in 2011. Its majorscientific goals include: (i) simultaneous multi-wavelength monitoring of intensity variationsin a broad range of cosmic sources; (ii)broadband spectroscopic studies of X-ray
binaries, AGN, clusters of galaxies and stellarcoronae; (iii) sky surveys in the hard X-ray andUV bands; (iv) studies of periodic and non-periodic variability of X-ray sources and more.ASTROSAT will carry five astronomy payloadsfor simultaneous multi-band observations. RRIis currently involved in the development ofLarge Area X-ray Proportional Counter (LAXPC)for X-ray timing and low-resolution spectralstudies over a broad energy band. One of thepayloads on ASTROSAT will consist of three ofthese identical LAXPCs.
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ASTROPHYSICS
Dark matter halos play a key role in today’smodels of galaxy formation and evolution. Adark matter halo is a hypothetical componentof a galaxy extending beyond its visibleboundaries whose existence is inferred by theeffect it has on the motion of the gas andstars in the galaxy. As part of his research incosmology and structure formation last year,Shiv SethiShiv SethiShiv SethiShiv SethiShiv Sethi studied supermassive black holeformation by direct collapse. He and hiscollaborators showed that the primordial gas inearly dark matter halos, with virialtemperatures just above 104K, could collapsedirectly to form a supermassive black hole(SMBH) if further cooling is avoided. Such ascenario is possible only in the presence of asufficiently strong primordial magnetic fieldwhich heats the collapsing gas. A dependenceof the evolution of the interstellar medium onthe temperature and strength of the magneticfield was derived.
By observing mergers of compact objects,future gravity wave experiments like DECIGO,BBO and LISA would measure the luminositydistance to a large number of sources with ahigh precision, but the same doesn’t apply totheir redshifts. Working with researchers fromIISc and IUCAA, Sethi looked at ways to reducesystematic uncertainties in determiningdistance-redshift relation using self calibrationtechniques. The group provided an analyticalexpression for the achievable accuracy andderived a lower limit on the total number ofsources that is needed to achieve this accuracythrough self-calibration.
Shiv Sethi, Biman Nath (RRI) and Vasiliev(Southern Federal University, Russia), recentlyconducted a study of the far-UV backgroundradiation spectrum with carbon lines inLyman-alpha clouds at redshift z=3 whichresulted in a paper being submitted to MNRASin Dec 2009. The effect of He II absorption inthe intergalactic medium at z=3 was studiedusing the available data of ionic ratios ofcarbon (namely CIII/CIV). Madau & Haardto
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predicted in 2009 that He II absorption wouldlead to a significant change in this ratio withrespect to standard ratios calculated so far,and this idea was tested with available data.The statistical analysis suggestsinhomogeneous abundance of He II at z=3,even extending down to z=2.5, indicating apatchy He II reionization.
Biman Nath’sBiman Nath’sBiman Nath’sBiman Nath’sBiman Nath’s research interests lie in the fieldof cosmology, structure formation andextragalactic astronomy. A paper submitted toMNRAS in Feb this year describes his work onextended X-ray emission from radio galaxycocoons. Nath developed a model in order tostudy the X-ray emission that has beenobserved in a number of FR-II type radiogalaxies. The model takes into accountinjection of relativistic electrons, their energylosses through adiabatic expansion,synchrotron and inverse Compton emission,and also the stopping of the jet after a certaintime. The evolution of the total X-ray power,the surface brightness, angular size of the X-ray bright region and the X-ray photon indexwere derived as functions of time and cocoonsize. The model predictions were comparedwith observations. The number of extended X-ray sources above a certain flux level in a givenportion of the sky was also estimated.
Gamma Ray Bursts (GRB), being the mostluminous electromagnetic events that occur inour Universe, keep stirring the scientificcuriosity of the astronomy & astrophysicscommunity. Recent observations of GRB showa lack of molecular hydrogen in the host
galaxies. Although a strong radiation field cancause this deficiency, these observationsbecome a puzzle when juxtaposed with thelargely observed abundances of other species,such as neutral magnesium, which can also bestrongly affected by radiation. Nath teamedup with researchers from Russia to investigatethe relative abundance of molecular hydrogenand Mg, first with analytical and semi-analyticalapproximations, and then with a full networkof reactions, in a variety of cases. During theyear, Nath has also worked closely with hiscolleague Sethi on various topics in the field ofcosmology and structure formation.
S Sridhar’sS Sridhar’sS Sridhar’sS Sridhar’sS Sridhar’s interests lie in the theoreticaldomain of galactic astrophysics. During the lastyear, he worked extensively on the physics ofthe dynamo action due to turbulence in shearflows. It is well-known that helical turbulenceleads to the growth of large-scale magneticfields (“dynamo action”). However, there areastrophysical settings in which large-scalemagnetic fields are seen in shear flows, butwhere the turbulence is expected to be non-helical. Recent numerical experiments on suchsystems have reported dynamo action, but thephysics underlying such a “shear-dynamo” isnot yet understood. Along with KandaswamySubramanian (IUCAA), Sridhar developed aformulation of the problem for a linear shearflow. The analysis, results and conclusions canbe found in a paper published in PhysicalReview E. Expanding on the same topic,Sridhar and his PhD student – Nishant Singhformulated the problem differently in order tostudy dynamo actions under various scenarios.Their work is submitted for publication to theJournal of Fluid Dynamics and Physical ReviewE. Currently, Sridhar is collaborating withKandaswamy Subramanian and Sanved Kolekar(IUCAA), addressing the dynamo problem inthe context of the so called “renovating flows”.The real advantage of this approach is that itallows the investigation of the shear dynamoproblem for arbitrary values of the magneticReynolds number and shear strength.
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Further understanding and a better theoreticaldescription of magnetohydrodynamic (MHD)turbulence is another active area of researchfor Sridhar. The motivation behind his work istwofold: (i) to offer a review of the currentstatus of our understanding of incompressibleMHD turbulence in a strongly magnetizedplasma; (ii) to present a new result, pointing ata certain new length-scale that could arise inthe imbalanced turbulence in the solar wind.The approach taken is phenomenological evenwhere a more rigorous theory is available, sothat a reader armed with paper, pencil andsome determination may be able to workthrough most of the physics.
The nuclei of most normal galaxies are thoughtto harbour supermassive black holes,surrounded by dense agglomeration of starsand gas. The stellar distribution can besignificantly anisotropic, as evident from thespectacular lopsided disc at the centre of theAndromeda Galaxy (M31). An idea Sridhar haspursued over many years, suggests that thesestellar systems could have originated throughthe development of a dynamical instability thataffects stars belonging to successive mergerevents. The instability is due to angularmomentum transfer, facilitated by the long-range gravitational interactions between thestars. Along with Tarun Deep Saini (IISc), hepresented a simple model that permits alargely analytical exploration of the counter-rotating instability. Their work is in-pressin Monthly Notices of the Royal AstronomicalSociety. The same line of research ismanifested in the collaboration of Sridhar withJihad Touma (American University of Beirut,Lebanon) where the goal is to ultimately
develop stellar-dynamical models for the nucleiof the Milky Way and M31. Using a verydifferent approach to the problem, they wereable to develop a largely analytical descriptionof the evolution of the dynamical instability.
RRRRRajendra Bhandariajendra Bhandariajendra Bhandariajendra Bhandariajendra Bhandari, who retired recently, hasworked for many years at RRI. His scientificcuriosity kept him active until his last workingday. During the last year, he has donetheoretical work in the field of reflectionmatrices, polarization transformations of lightand non-modular topological phases.
Propagation of polarized light through anoptical system inevitably involves reflectionsfrom arbitrary surfaces resulting intransformation of the polarization state oflight. Such transformations are described by2x2 complex matrices which are fairlycomplicated functions of parameters of thereflecting medium. Recently some constraintsarising from the principle of reciprocity whichmust be satisfied by such matrices werederived and their use as a tool to test derivedexpressions for such matrices was suggested.The tool was applied to several reflectionmatrices published in literature and in twoinstances involving media with optical activitythe derived matrices were found to be in errorthus establishing the usefulness of the tool.
Last year, Bhandari worked on an inverter forpolarization transformation. Sandwichconstructions consisting of a sequence oftransparent or absorbing polarization-changingelements for performing desiredtransformations on polarized light have beenimportant tools for a variety of applications inoptics. It was shown recently that an SU(2)polarization element sandwiched between twoorthogonal halfwave plates at 45o, produces atransformation which is inverse of thatproduced by the original element. This resultwas generalized to (i) pure dichroic elementsand (ii) elements which have dichroism as wellas birefringence with the same polarizationeigenstates. With electrically switchablehalfwave plates this provides a simple way to
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rotate a linear polarizer through 90o remotelyand at high speed without any moving parts.
OBSERVATIONAL ASTRONOMY &INSTRUMENTATION
K S Dwarakanath’sK S Dwarakanath’sK S Dwarakanath’sK S Dwarakanath’sK S Dwarakanath’s research activitiesthroughout last year were guided by his longlasting interest in extragalactic astronomy andclusters of galaxies. He and his PhD studentRuta Kale presented a multi-wavelengthanalysis of the merging rich cluster of galaxiesAbell 2256. The galaxy cluster A2256 wasobserved at 150 MHz using the GiantMetrewave Radio Telescope (GMRT) and adiffuse radio emission over an extent of abouta million light year was detected. Using this150 MHz image and the images from thearchival observations from the Very Large Array(VLA) at 1369 MHz and the WesterborkSynthesis Radio Telescope (WSRT) at 330 MHz,images of the ratio of the intensities (spectralindex) of the diffuse radio emission atdifferent frequencies were produced. Thespectral index values of the diffuse emissionshow variations across the cluster. Thesespectral indices indicate synchrotron life timesfor the relativistic plasmas from a mergerevent within the last 0.5 gigayear or so. Thediffuse emission is generated by theturbulence injected by such a merger event.Furthermore, the diffuse radio emission shows
spectral steepening towards lower frequencies,which is unusual. This low frequency spectralsteepening is consistent with a combination ofspectra from two populations of relativisticelectrons created at two epochs (two mergers)within the last ~ 0.5 gigayear. The lowfrequency observations are proving to be veryimportant probes in understanding thedynamics of clusters.
Dwarakanath has also been collaborating withastronomers Chandeyee Sengupta and D JSaikia from NCRA in understanding aninteracting system of galaxies. Observations ofatomic hydrogen (HI) with the GMRT of theinteracting galaxies NGC5996 and NGC5994,which make up the ARP72 system were carriedout. Arp72 shows a complex distribution of HItails and bridges due to tidal interactions. Theregions of high HI column density in the bridgeof emission connecting the two galaxies, whichis also seen at optical, infrared and ultravioletwavelengths is in the range of 1.7-2X1021
atoms cm-2. An eastern tidal tail with HIcolumn densities in the range of 0.8-1.8X1021
atoms cm-2 is seen prominently in the GALEXsatellite image at ultraviolet wavelengthsindicating regions of massive star formation.Further studies involving kinematics of ionizedand molecular gases with a view to obtain amore comprehensive picture of this interactingsystem is in progress.
Radio galaxies triggered a long-lasting interestin LLLLLakshmi Saripalliakshmi Saripalliakshmi Saripalliakshmi Saripalliakshmi Saripalli and havebeen a primary focus in herresearch career. Radiogalaxies manifest in severaldifferent extended radiostructures. The most typical isthe twin lobe structure, butsome radio galaxies exhibit avariety of lobe morphologies(double-double, X-shapes andgiant-lobe radio galaxies). Theorigin of these lobemorphologies is not wellunderstood. Major part of
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Saripalli’s work this year was prompted by thediscovery of the unusual radio galaxy B2014-558, whose observed X-shaped structure couldnot be explained by the existing set of models.The relationships between the radiomorphology in double radio sources and theradio-optical position angle offset (the relativeorientation of the radio axis with respect to themajor axis of the host galaxy) were examinedfor a representative sample of radio sources(the nearby 3CRR sources), and separately forsamples of giant radio sources and X-shapedradio sources. The observations of thedependence of radio morphological featureson the radio-optical position angle offset, andon whether the radio-source axis is closer tothe host major or minor axis, were published inthe Astrophysical Journal, with RaviSubrahmanyan as a co-author.
A paper titled “ATLBS: the Australia TelescopeLow-Brightness Survey” was published this yearas a result of the collaboration between RaviSubrahmanyan, Lakshmi Saripalli, Ron Ekers(CSIRO ATNF) and Elaine Sadler (University of
Sydney). It presents a radio survey carried outwith the Australia Telescope Compact Array(ATCA). The survey was prompted by the needto make a complete inventory of the diffuseemission components as a step towards astudy of the cosmic evolution in radio sourcestructure. The Australia Telescope Low-Brightness Survey (ATLBS) at 1388 MHz covered8.42o2 of the sky in an observing modedesigned to yield images with exceptionalsurface brightness sensitivity and lowconfusion. The observations provided ameasurement of the complexity and diffuseemission associated with mJy and sub-mJyradio sources.
The areas of scientific exploration for NNNNNUdayashankarUdayashankarUdayashankarUdayashankarUdayashankar include sky surveys as well asinstrumentation and signal processing for radioastronomy. Last year, his research activitiescontinued in the same direction. An all skysurvey at 150 MHz using the Mauritius RadioTelescope (MRT) is under way where the surveyis expected to image approximately 4.8 sr(steradians) of the southern sky. This survey isan expansion of a previous one which coveredapproximately 1.2 sr. Work related to imagingand source extraction for the remaining 3.6 srof the sky has been carried out by SootashDaiboo and Arvind Nayak. The array geometrywas re-established, new calibration tables, andnew point-source functions (PSFs) fordeconvolution were generated. To improve thecalibration technique, a field of view calibrationscheme was developed, which uses MRTimages of the sky one sidereal hour prior tothe data selected for imaging. With these newdevelopments imaging of an additionalsteradian of the sky was completed with anaverage noise reduction of about 20%.
Four low frequency receiver systems weredeveloped in RRI and installed on four of theGMRT antennas. Based on their satisfactoryperformance, a proposal was submittedseeking guaranteed time of around 600 hoursfor an all sky survey at 50 MHz. Collaboratorsof Udayashankar on this project areDwarakanath (RRI), S.K. Sirothia (NCRA) and Y.
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Gupta (NCRA). On approval of this proposal,thirty receivers and feeds required for thissurvey will be built. The commissioning(expected to take about a year) and the surveywill be carried out jointly by the NationalCenter for Radio Astrophysics (NCRA) and RRI.The expected sensitivity is an order ofmagnitude better than that of the best low-frequency survey available to date (the VLALow-Frequency Sky Survey at 74 MHz). It is alsocomparable to the sensitivity of the 1.4 GHzVLA Sky survey (NVSS) done by the NationalRadio Astronomy Observatory, USA.Furthermore, this survey is expected to besensitive to low surface brightness andextended features that are likely missing inother surveys. A variety of studies involvingsources in the Galactic plane, diffuse extendedextragalactic sources, spectra of extragalacticsources and source counts are expected to becarried out with this survey data. The finalproducts of the survey (images and sourcecatalogues) will be made available on theWorld Wide Web within 12 months from thedate of completion of the last successfulsurvey observations.
Teamed up with the Mechanical Engineeringgroup at RRI, Udayashankar is working on thedevelopment of 15m parabolic dish antennas.Preliminary design studies showed conclusivelythat there was no specific advantage inpreloading a dish with regard to obtaining alesser weight-per-unit-area. A detailed designstudy of a 15-m Bent Spoke Dish, which usesplastic bent spokes for the backup structurewas completed and documented in a technicalreport. Examination of the feasibility of usingelectromagnetically transparent fiberglassstructural members for the quadripod, andadding a third axis of rotation to minimize theproblems of polarization calibration is underdiscussion with a consultant.
RRI is a collaborator in the internationalMurchison Wide Field Array (MWA) project.Udayashankar, Deshpande, Subrahmanyan andVedantham, who joined recently, have been
working on the assessment of drift-scanstrategy for the detection of Epoch of Re-ionization (EoR) signal. RRI team has carriedout observations of three regions of the skyusing the MWA 32-tile system to compare theexpected and the measured sensitivities intracking and drift scan modes. Data analysis isunder progress.
Currently, Avinash DeshpandeAvinash DeshpandeAvinash DeshpandeAvinash DeshpandeAvinash Deshpande is working witha group of astronomers from the USA andMexico in an attempt to better understandand analyze OH masers. Masers are a type ofastrophysical sources of stimulated spectralline emission, typically found in the microwaveportion of the electromagnetic spectrum.W49N is one of the most luminous regions ofactive star formation in the Galaxy. A 12-hoursynthesis OH-line data from the Very LargeBaseline Array (VLBA) telescope, in thedirections of W49N and W3OH, were obtainedand are currently being analyzed. The detailedhigh angular-resolution images at 1612, 1665and 1667 MHz reveal scattered broadened OHspots, indicating anisotropic scattering, withthe position angles of the spot images
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oriented perpendicular to the galactic plane.This is interpreted in terms of scattering due toelectron-density irregularities being orientedparallel to the galactic plane due to influenceof similarly aligned local magnetic field. Furtherinvestigations are in progress.
Deshpande is a part of a large team ofresearchers, engineers and students from RRIand Green Bank Telescope at the NationalRadio Astronomy Observatory (NRAO), USA,who have developed a multi-band receiver(MBR) for pulsar observations. The MBR systemwill enable tomographic study of pulsaremission. The receiver system was designedand built at RRI, and is now mounted on theGreen Bank 110-meter telescope. It consists ofa multi-band feed with 10 spectral bands from100 to 1600 MHz, an RF front-end, and tencomputer-controlled receivers, each cateringto one band. The receivers consist of a high-gain heterodyne receiver chain, digitizers, andan FPGA-based back-end, enabling raw-voltagerecording of dual-polarization data with 16MHz bandwidth. The design of suitable dual-polarization feed for multi-band operation wasdone. A feed-testing facility was developed atRRI’s field station in Gauribidanur, andspectrum analyzer based procedures formeasuring antenna parameters weredeveloped. After suitable software andhardware upgrades were incorporated andtested at Gauribidanur, the MBR system was
shipped to Green Bank. It was installed andinterfaced with the GBT fiber-link, and the firstlight observations was successfully made on1st June 2009. Pulsar observations were madeduring July and August and the detailedanalysis of these data are in progress.
Harish VedanthamHarish VedanthamHarish VedanthamHarish VedanthamHarish Vedantham recently joined the Instituteand have since been actively involved in theMWA project. MWA belongs to a newgeneration of low frequency interferometricradio telescopes and it’s currently beingcommissioned in the interference free WesternAustralian desert. Working with RaviSubrahmanyan and Udayashankar, Harish istrying to process MWA data to understand themerits and demerits of different observing,calibrating, and data processing strategies. Thiswill eventually lead to estimating the statisticsof spatial 3-dimensional fluctuations in the21cm signature from the Epoch ofReionization. Such studies will bridge a gap inour understanding of the early evolution ofthe universe and consequently constrain/improve current cosmological models.
Research interests and endeavors of theinstitute members stretch to the sub-millimeter portion of the electromagneticspectrum. B RB RB RB RB Rameshameshameshameshamesh has proposed a newoptics design that allows for building large sub-millimeter telescopes very economically. Theconstruction of a 3m SubmillimeterwaveTelescope Prototype (3mSTeP) based on such
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design is under way. The mechanical structuredesign and optimization were completed lastyear. Work on the 8 GHz widebandspectrometer for the 3m STeP is nowunderway. Given that velocity range coveredby a spectrometer is proportional to itsfractional bandwidth, sub-millimeter waveobservations require wideband, coarseresolution spectrometers. A detailed design ofthe IF processor and the sampler-DSP boardwas undertaken to ensure useful, timely andeconomical realization of the spectrometer. Byefficiently choosing the local oscillatorfrequencies and using direct digitization, theprocessor has been designed to minimize thenumber of local oscillators and filters required.The driving system for the 3m STeP is yetanother challenge. A new circuit design withhigher power efficiency, and reduced numberof component compared to the commercialPWM drive systems was designed,implemented and tested to work at therequired 20V output voltage. A stand-aloneunit with special purpose PCB made for thisapplication was also built.
Biswajit PBiswajit PBiswajit PBiswajit PBiswajit Paulaulaulaulaul and his students at theAstronomy and Astrophysics Group stepped inthe yet unexplored area of X-ray polarizationmeasurements. Such measurements will largelyenhance our understanding of severalimportant high energy astrophysical problems.Large amount of time and effort were spent inthe last year on the development of an X-raypolarimeter. Modifications of the initial design
were carried out to improve the efficiency ofthe system. At present, resistive wires in the X-ray detectors allow for position determinationand spectral measurements. Much attentionwas paid to the development of efficientprocessing electronics system. An FPGA basedcoincidence and anti-coincidence logic system,and simultaneous charge measurement systemhave been developed and tested successfully.As a result, the processing electronics unit ofthe polarimeter was reduced and theprocessing power increased. Simulations fordesign optimization and preliminary tests ofthe cylindrical proportional counter detectorfor a Thompson X-ray polarimeter were alsocarried out during the year. Majorcontributions to this work come from theengineers in the X-Ray Astronomy Lab at RRI.
Paul serves as LAXPC representative in theASTROSAT Ground Segment Committee thattakes care of all ASTROSAT activities other thanthe hardware development. Working closelywith two teams at ISAC, Bangalore and SAC,Ahmedabad, he designed the data reductionpipe-line for LAXPC and is currently workingtowards preparation of the data formats ofthe ASTROSAT-LAXPC, both at the intermediateand user distribution level.
In the area of observational astronomy, thescientific research of Paul includes pulsars,active galactic Nuclei (AGN) and transients.Working alongside scientists from Physical
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Research Lab (PRL), Ahmedabad and DelhiUniversity, Paul analyzed the recent step likeflux enhancement in the X-ray pulsar 4U 1626-67. The analysis of the data from theProportional Counter Array (PCA) instrumentcarried on Rossi X-ray Timing Explorer (RXTE)showed that the persistent MHz quasi-periodicoscillations in this source disappeared after theflux change, and the X-ray spectrumconsiderably changed.
Another study of the binary pulsar KS1947+300 was done using data from the sameinstrument and quasi periodic oscillations(QPO) at 0.02 Hz were discovered. Paul and hiscollaborators argue that the detection of QPOsand strong pulsations at a low luminosity levelsuggest that the magnetic field strength of theneutron star is not as high as was predictedearlier.
Paul was also a collaborator in the study of theX-ray emission from the nuclear region of the
low-surface-brightness (LSB) galaxy UGC 6614.The X-ray properties and spectra of the centralobjects in LSB galaxies are yet to be activelyexplored. XMM-Newton archival data was usedto study the characteristics of the X-rayspectrum and flux variability of the activegalactic nuclei (AGN) of UGC 6614. The resultsof this study demonstrated that, although LSBgalaxies are poor in star formation, they mayharbour AGNs with X-ray propertiescomparable to those seen in more luminousspiral galaxies.
Paul’s research last year also included dataprocessing and analysis of data from threedifferent instruments (Swift-BAT, RXTE-ASM andIntegral-IBIS) to carry out a detailed orbitalmodulation study of three high mass X-raybinaries (HMXB).
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Lightand Matter
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Lightand Matter
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The Light and Matter Physics (LAMP)group consists of four highlymotivated faculty members andtheir students that started in 1995.Interactions between light andmatter are ubiquitous in theUniverse! Understanding thepatterns and mechanisms of theseinteractions, and their governinglaws reveals many secrets about thenature of both light and matterindividually. Solid fundamentalunderstanding of such interactionsopens up to an enormous field ofpotential applications, ranging fromdetection of gravitational waves tolaser based medical imaging. Themembers of LAMP group combineknowledge from atomic, molecular,linear and nonlinear optical physicsto study classical and quantum light– matter interactions. One uniquefeature of the group is its holisticscientific approach, wheretheoretical, numerical andexperimental research complementeach other. There are three labs forlaser cooling and trapping cateringto the individual needs of the LAMPmembers. A laboratory is set up tostudy light propagation in randommedia, and experiments areconducted regularly in both thenonlinear optics lab, and laser-induced plasma lab.
The following pages summarize themajor areas of research for the LAMPgroup. Each member’s individualwork during the last year is providedin the next section, giving the readermore detailed and technicaldescription of their respectiveresearch activities.
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QUANTUM OPTICS
Quantum optics is a field in physics that appliesquantum mechanics to study light phenomenaand light-matter interactions. Since the firstindication that light may be quantized in 1899,the field of quantum optics has witnessedsignificant progress in our understanding oflight-matter interactions and microscopicsystems. Today’s major fields of interest inquantum optics include manipulation ofelemental particles like atoms, ions andmolecules, and the use of quantum optics forquantum information. The LAMP group hasadopted a basic science research approach, asopposed to a competitive technologydevelopment approach, in keeping with theoverall philosophy of the Institute.
LASER COOLING AND TRAPPING
Laser cooling and trapping is an area ofphysics that has largely expanded over thelast decade. Presently, atoms can becooled down to extremely low kinetictemperatures (as low as 1µK) and trappedfor a time period on the order of seconds.Such control over the motion of atomsallows researchers to probe their behaviormore precisely than ever before. There area number of techniques to cool and trapatoms of alkali elements and the mostcommonly used is called Doppler cooling. Itinvolves three mutually perpendicular laserbeams that intersect at the centre of thechamber. A pair of magnetic coils producea magnetic field that is zero at the centre
of the chamber, and increases radiallyoutward. Using appropriate wavelengthand polarization of the laser beams,atoms can be cooled by repeatedabsorption and emission of light, andtrapped by an inward force arising out ofthe combination of the polarised lightbeams and the spatially varying magneticfield. Such a system is called MagnetoOptical Trap or simply, MOT.
2D MOT – Researchers from the LAMPgroup are continuing their work on theconstruction of a 2 dimensional MOT.Currently, they are involved in the processof installing and testing the coils thatproduce the magnetic force in the MOT.
MOT and Quantum Logic - Quantum logic isan attractive area of research for the LAMPgroup. With the ever shrinking electronicdevices, quantum effects like superpositionand entanglement cannot be ignored andnew ways of defining the basic states of 0and 1 should be investigated. To achievequantum logical gates, the atoms need tobe cooled and trapped in optical lattices,such that the 0 and 1 states of a digitalcircuit can be mapped to internal states ofthe atom. The inducing of conditionaltransitions between these states is theequivalent of a logical gate. Currently, aMOT with the capability of trappingindividual atoms is being built at RRI.
A Lattice of Ion Traps – Researchers at RRIhave proposed a novel ion trapconfiguration which allows for highprecision spectroscopy measurements,quantum information processing as well asnew studies of few-particle interactionsystems.
Ion-Atom System – Attempting thesynthesis of ultra cold molecules from ultracold atoms (with the emphasis on dipolarmolecules), LAMP members haveconstructed and fully characterized thenecessary experimental system that is
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capable of trapping both atoms and ionswithin the same region of space.
A novel technology for laser cooling andtrapping – the LAMP group at RRI is alsoengaged in the construction of a systemcapable of trapping atoms, ions, moleculesand photons. Such a system will createopportunity to study quantum mechanicaleffects in cold atoms/ions/molecules andexpand our knowledge of ultra-coldmolecular physics.
ELECTROMAGNETICALLY INDUCEDTRANSPARENCY (EIT)
EIT is a quantum mechanical phenomenon,where under specific conditions, anabsorption line of a material can becancelled, changing it from opaque totransparent at that particular frequency. Toobserve EIT two highly coherent lasers aretuned to interact with three or morequantum states of the material. Since 1990considerable research activity has beendevoted to the topic of EIT. RRI researchersare trying to build a strong fundamentalunderstanding of the EIT phenomenon,using both theoretical and experimentalmethods.
QUANTUM WALK OF LIGHT
A random walk is a mathematicaldescription of a trajectory, where thesuccessive steps are random. Classicalrandom walks are used in searchalgorithms when the searched parameterspace is random. They find application in
the fields of computer science, physics,ecology, economics and psychology.Quantum walks are the equivalent ofrandom walks in quantum computing andcan form a part of a quantum algorithm.LAMP group members are nowinvestigating quantum walks of light infrequency space.
LIGHT PROPAGATION INRANDOM MEDIA
Multiple scattering of light in random media,like fog, considerably reduces visibility.Researchers at RRI have developed a techniquefor imaging in turbid media, which is currentlybeing tested for commercial applications likeaircraft navigation.
The localization of light in random media is aphenomenon, which is not well understood.After extensive simulations, members of theLAMP group are now attempting toexperimentally observe localization of light,using ferrofluids as a medium. Ferrofluidsconsist of a fluid (usually water) withferromagnetic nanoparticles, that act likerandom scatterers, when dispersed in it. Theeasy manipulation of nanoparticles inferrofluids, allows to test quickly variouspossible scenarios that lead to localization oflight. The understanding of this phenomenoncan open doors for future novel opticaldevices.
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NONLINEAR OPTICS
When a material is probed with a very highintensity optical field, responses like reflection,transmission and absorption no longer scalelinearly with the intensity of the applied field.Nonlinear optics is a branch of optics thatstudies such nonlinear effects in variousmaterials. It forms a broad field of research,with device applications intelecommunications, optical storage and alloptical computing. Optical switches, saturableabsorbers and optical limiters are just fewexamples of devices based on the principle ofnonlinear transmission. The LAMP group at RRIinvestigates the nonlinear optical properties ofvarious types of materials, with an emphasison nanoparticles and nanocomposites. Tostudy the temporal behavior of nonlinearities,the group uses femtosecond pump-probespectroscopy. Other frequently usedexperimental techniques used pulsed laser z-scan, degenerate four wave mixing (DFWM)and white light z-scan.
LASER INDUCED PLASMA
Lightning is a beautiful (and often dangerous)example of how Nature can create plasma.Today, the technological evolution of lasersallows researchers to routinely generateplasma in their labs, using very high powerpulsed lasers.
Naturally, such plasmas are called laser inducedplasmas and they find application in manytechnological fields. In material science, PulsedLaser Deposition is the most commonly usedtechnique for thin film production. Opticalemission spectroscopy of a laser inducedplasma, called Laser Induced BreakdownSpectroscopy (LIBS), is a powerful techniquethat provides immediate elemental analysis ofany matter, regardless of its physical state.LIBS is widely used for the detection of heavymetals in soil, aerosol characterization, culturalheritage elemental analysis, process control inindustry, space exploration, etc. Laser inducedplasmas are also used in the field of medicaldiagnosis and surgery, laser ignition, propulsionand fusion. Researchers from the LAMP groupconduct a large number of experiments tostudy the time evolution and spectralcharacteristics of laser induced plasmas. Thetargets used can be solid or liquid samples andthe experiments are performed in vacuum aswell as in ambient pressure condition.
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QUANTUM AND CLASSICALOPTICS
The 3GHz magnetic dipole transition betweenground hyperfine levels of Rubidium 85 isfamous for the clock resonance in Rubidiumclocks. Andal Narayanan’sAndal Narayanan’sAndal Narayanan’sAndal Narayanan’sAndal Narayanan’s group at RRIfabricated a 3 GHz microwave cavity in order tostudy the possibility of coherent transfer link,namely microwaves-optical waves-matter link,during an electromagnetically inducedtransparency (EIT) phenomenon. First, thecoherence of the microwave field getstransferred to the optical domain and thenusing EIT it is transferred again quantummechanically to the matter. This is possiblebecause EIT is a quantum mechanical effectwhich preserves coherence. Last year,Narayanan was engaged with the fullcharacterization of the custom build 3 GHzmicrowave cavity. The quality factor Q of thecavity was measured to be as high as 4000. Atthe center frequency, the required specialmode was successfully coupled with highefficiency and good signal to noise ratio.Testing of the temporal range of efficientcavity coupling is under way.
Narayanan and the visiting researcher M.Manukumar from Bangalore University havefound an experimental signature that uniquelyidentifies interacting superposition states ofinternal levels of Rubidium. The experimentswith Rubidium atoms were done at roomtemperature in a vapour cell. The observedsignature is qualitatively similar to the fringepattern in a Young’s double slit experiment.The “visibility” of the fringe pattern helps toidentify spectral positions of interacting statesof equal strength. It’s envisioned that thisresult will eventually hold for true quantumsuperposed states of light and matter.
Simulations of microwave based quantumoptical experiments are another active area ofresearch for Narayanan. A density matrixnumerical calculation was carried out forvarious coupling schemes of Rb 85, addressingthe question of the relative phase coherenceo
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of phase sensitive signals, involving bothmicrowave and optical light fields. Thepossibility of squeezing the quadrature noisebelow the quantum limit is currently beinginvestigated. A novel EIT scheme involving twophoton optical resonance and a microwavefield is studied. The next step is to use thesecalculations to experimentally test these resultsin the laboratory.
The successful microwave and roomtemperature experiments have been theprimary, but not only focus of Narayanan’sresearch last year. The building of coils for atwo dimensional magneto optical trap (MOT)has started recently. This new setup willincrease the total number of atoms available inthe trap – a condition required for theenvisioned future cold atom experiments inquantum optics.
Quantum computing is one of the majorresearch interests of Hema R Hema R Hema R Hema R Hema Ramachandranamachandranamachandranamachandranamachandran.She has conducted both theoretical andexperimental work in the field of quantumwalks. The theoretical investigation of a onedimensional Hadamard walk by cold atoms in adouble optical lattice, has now been published.This work discusses the parameters underwhich present day experimental capabilitiespermit observation of this phenomenon. Lastyear, her team studied the quantum walk oflight in a simple tabletop experiment using theanalogy with the classical interferenceexperiment. For demonstrating the quantumwalk of a photon in frequency space, aMichelson interferometer was modified by (i)
replacing the conventional beam splitter by apolarizing beam splitter and (ii) shifting thefrequency of light in one path up by a certainamount and down by the same amount in theother path. A cascade of such modifiedinterferometers was arranged, and the finalinterference pattern was the manifestation ofa quantum walk.
Hema Ramachandran’s work towards quantumlogic with cold atoms, involved the setting upof a magneto optical trap (MOT) with theability of trapping individual atoms within theMOT. Trapping of individual atoms can beachieved using a very tightly focused laserbeam that forms a steep dipole trap. It wasfound that for the size and position of the lensthat produces the required focused light theMOT beams must be inclined at about 60º,rather than the usual 90º. This made the beamalignment and intensity matching quitechallenging. Success was reported in trappingmultiple atoms with beams inclined at suchangles.
Multiple scattering of light in a random medialike fog, or muddy water, considerably reducesvisibility. Ramachandran, Mehdi Alouini(University of Rennes) and Fabien Bretenaker(Univeristy of Paris) have developed atechnique for imaging in turbid media thatoffers simplicity of implementation. Anexperiment was designed to find out whetherthis technique could be utilized for navigation
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of aircraft under reduced visibility. A polarizedlight source is to be placed on top of a hightower (TV tower in Rennes, France), andpolarization based imaging optics in alaboratory 2 kilometers away. The intention isto study the feasibility of imaging undervarious extents of visibility. The early morningfog which is present at Rennes for nearly sixmonths of the year makes it ideal for suchexperiments.
In an effort to understand the puzzlingabsence of transmission and apparent storageof light reported in a medium comprisingnanometric and micrometric magneticspheres, Ramachandran has taken up asystematic study of the light transmissionproperties in a ferrofluid as a function of fieldand the polarization state of light. It was foundthat as light transmission decreases, it isactually scattered sideways, or normal to itsinitial direction of propagation. The role of thelarger magnetic particles is now beinginvestigated.
As part of her research on novel opticalapplications of nanomaterials, during a recentcollaboration with Deepak Mathur (TIFR) onlight emission by carbon nanotubes (CNTs),Ramachandran observed the formation ofbubbles in the surrounding fluid. Thesebubbles could be trapped at the tweezerfocus. Their formation was attributed to thephoto-thermal heating of the CNTs and itsvicinity, leading to the expulsion of hot gasfrom within the CNTs and vaporization of theimmediate surrounding fluid. CNTs, which areusually repelled by the tweezer focus due tothe dipole force, were now found attractedtowards the bubbles; they adhered to thebubble surface and could thus bemicromanipulated. This suggested the possibleuse of the microbubbles as scavengers ofCNTs. The effect was demonstrated in staticcondition as well as fluid flow, both in thedirection of flow and against it.
QUANTUM INTERACTIONS
Sadiq RSadiq RSadiq RSadiq RSadiq Rangwala’sangwala’sangwala’sangwala’sangwala’s group conducts scientificand experimental research in the field ofquantum interactions. In their paper titled“Three-dimensional Lattice of Ion Traps”, theypropose and numerically characterize an iontrap which is three dimensionally symmetric.Individual traps can in addition be stacked in atight packed arrangement. Such aconfiguration will open the door to a fresh setof possibilities for future experiments withhighly symmetric and multiple ion traps. Sucha system could be of great value, as the limitednumbers of ions available to work withrepresents a serious constraint for severalexperiments. It is numerically demonstratedthat neighboring traps have little effect oneach other for the purposes of severalpotential applications. Specifically therelevance of this trap to “ion clocks”,“quantum information processing” and “few-particle interacting systems” are discussed intheir paper. Extensions of this concept tomany applications in fundamental and appliedphysics and for applications requiring lowersymmetry are also possible, as suggested byRangwala’s group.
A major project of the group was the buildingand full characterization of the ion-atomexperimental system. The experimentalobservations and results include: (i) thesuccessful and simultaneous trapping of coldatoms 85Rb and ions 85Rb+ ; (ii) successfuldetection of the effect of trapping the ions in
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the presence of cold atoms on both- the ionand the atom signals; (iii) reliable estimation ofthe number of atoms and ions; (iv) successfulmeasurement of the temperature of the ionsin the trap. The detection technique for theions, though unusual for this class ofexperiment, is robust and reliable. Future plansinclude the synthesis of ultra cold moleculesfrom the ion-atom mix, measurement of theion-atom collision cross-sections, mixedspecies ion atom experiments, as well as thehighly challenging optical, non resonant,detection of trapped ions.
Sadiq Rangwala’s cold molecules projectrequires extremely low light level detection.The most sensitive detection technique todayis resonant detection via cavities. Beforeattempting cold molecule detection, thetechnique must be tested on hot and thencold atoms. Two experiments with Rb 87 wereperformed where the transmission propertiesof a cavity containing atoms were studied.Several interesting features in the laser-atom-cavity system have been explored.Interestingly, it was found that transmission ofthe resonant light into the cavity mode can becompletely switched OFF and ON byaddressing the atoms in the cavity with a sidelaser. For negative or positive logic switching,the two laser beams (cavity mode and sidelaser) must resonantly connect the excitedstate manifold to two distinct or equal groundstates, respectively. No specific alignment isrequired for the side beam, just that itintersects the cavity mode at one spot. Afterthe experiment, the theoretical model thatexplains the qualitative features of theswitching has been constructed. Futureenvisioned experiments include positive andnegative logic switching with atoms in paraffincoated cells and switching experiments withpotassium. This project is done in collaborationwith researchers from University of Californiaat Berkeley.
For the past several years Sadiq Ranqwala’sgroup is also working on a system capable oftrapping cold atoms, cold molecules, cold ions
and photons. Major science objectives areCa+ ion trapping, molecule synthesis byphoto-association, trapping of 39K or 40K inthe cavity (MOT), using cold Rb atoms toperform the switching experiments and more.The system was constructed and tested in theperiod of June-November last year. The mostsensitive part, the Fabry-Perot cavity inside thevacuum system, performed significantly betterthan expected. Currently, a small slackness inthe ion trap structure prevents experimentalwork in vacuum. The redesigned version of thesystem is expected to start soon.
Sadiq Ranqwala is part of an internationaleffort towards a more detailed investigation ofanti-relaxation coatings for alkali-metal vaporcells using surface science techniques. Manytechnologies based on cells containing alkali-metal atomic vapor benefit from the use ofanti-relaxation surface coatings in order topreserve atomic spin polarization. In particular,paraffin has been used for this purpose forseveral decades and has been demonstratedto allow an atom to experience up to 10,000collisions with the walls of its container withoutdepolarizing. Modern surface and bulktechniques were applied to study paraffincoatings, in order to characterize theproperties that enable the effectivepreservation of alkali spin polarization. Thesemethods include Fourier transform infraredspectroscopy, differential scanning calorimetry,atomic force microscopy, near-edge X-rayabsorption fine structure spectroscopy, and X-ray photoelectron spectroscopy.
LASER INDUCED PLASMA ANDNONLINEAR OPTICS
Laser induced plasma is one area of expertisefor R R R R Reji Philipeji Philipeji Philipeji Philipeji Philip. This year his research wasfocused on spectroscopic studies of laserinduced plasma. The ultrafast laser-inducedplasma was generated from solid (Nickel) orthin film targets. In the case of solid targets,the X-Ray and gamma ray emissions wereobserved, while for thin film targets Philip
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looked at the visible emissions. A hundredfemtosecond laser pulses of 10 mJ energyfrom a Ti:Sapphire laser were focused using a60 cm plano-convex lens at the target, whichwas kept in vacuum. The target was movedbetween successive laser shots using a targetmanipulator so that the plasma was generatedfrom a fresh surface every time. The resultingpeak intensity was about 1015 W/cm2. Acalibrated detector was used to collect thespectra, and the hot electron temperature wascalculated from the Bremsstrahlung emissionspectrum. The electronics and softwarerequired for the target manipulator weredeveloped in-house. The equipment neededfor spectroscopic investigations of plasmaproduced from thin film samples wascompleted in collaboration with the Institute ofPlasma Research. An additional vacuumchamber was attached to the existingchamber. Using a three-wire Langmuir probe,ion and electron current measurements fromthe thin film plasma were carried out. Thepreliminary measurements showed that theplasma was not consistent. Currently, ways ofimproving the plasma consistency are beinginvestigated.
Philip actively studies the nonlinear opticalproperties of nanomaterials and other media.Collaborating with experts, who synthesizedthe various materials required for this study,Philip investigated the optical nonlinearity ofdifferent types of media, using the openaperture z-scan experiment. These includeorganics, inorganics, semiconductor quantumdots, metal nanoparticles, andnanocomposites. Some of these materialswere found to be potential candidates foroptical limiting and photonic deviceapplications.
Conventionally, a tunable laser is needed tomeasure the wavelength dependence ofoptical parameters with spectral dispersion.However in some cases, a white lightcontinuum may be a suitable substitute for thetunable laser. The white light continuum is anintense broadband emission obtained frommedia like photonic crystal fibers, when theyare excited using an ultrafast laser. It has alarge spectral extent ranging from the UV to IRregion with high intensities and short timescales. If white light continuum is used as thesource, the dispersion of optical nonlinearitiesover a range of wavelengths can be measuredin a single z-scan experiment. Philip’s grouphas set up the white light z-scan experimentand a few measurements have been done. Itwas found that the intensity of the continuumwas spread over a large wavelength range,leading to lower S/N ratios. Improvement ofthe set up is now under way.
Sunita SharmaSunita SharmaSunita SharmaSunita SharmaSunita Sharma joined the LAMP group as apost-doc focusing her research onnanomaterials, solar cells, biosensors andnonlinear optics. Exploring the vast potentialfor applications of nanomaterials in solar cellsand optoelectronic devices, Sunita works onreducing wafer thickness, and improving thequantum efficiency of solar cells.
In line with her research on biosensors, Sunitaconducted morphological (X-Ray Diffractionand Differential Scanning Calorimetric) andoptical (Fourier Transform Infrared and UV-Visabsorption) studies of silica matrices withentrapped Rhizobial (Rz) structure. Hercollaborator was Mr. Sandeep Menon fromMacquarie University Sydney, Australia. Sol-gelderived silica has tremendous applications as abiocompatible scaffold for the immobilizationof cells. The use of xerogel as a matrix in theblueprint of biosensors is an appealingproposition due to several inimitablecharacteristics of xerogels like their highporous nature, amendable pore size, andexceptionally large internal surface area.
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The Soft Condensed Matter (SCM)group was for a long time calledLiquid Crystals group with its researchactivities concentrated in the area ofliquid crystal synthesis,characterization and other analysis oftheir physical properties. During theforty years of its existence the grouphas made important contributions tothe field of liquid crystals. Keeping thefocus on fundamental research, thegroup has recently expanded itsactivities to investigate other softcondensed matter like polymers,colloids, amphiphilic systems andnanocomposites. Theoretical andexperimental research today includesthe well established area of liquidcrystal synthesis and characterizationas well as electrochemistry andsurface science, liquid crystal displays,rheology studies of soft condensedmatter and biophysics. The researchenvironment in the SCM group ishighly interactive with constantknowledge sharing and exchange ofideas among chemists,electrochemists, condensed matterphysicists, theoretical physicists andmembers with statistical physicsexpertise.
The following pages summarize themajor areas of research for the SCMgroup. Each member’s individual workduring the last year is provided in thenext section, giving the reader moredetailed and technical description oftheir respective research activities.
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LIQUID CRYSTAL SYNTHESIS
A liquid crystal is a liquid whose atoms ormolecules are regularly arranged in one or twodimensions such that it exhibits some opticalproperties associated with crystals. Liquidcrystals exist in the so called mesomorphicstate, or a state of matter between liquid andsolid. A mesogen is the fundamental unit of aliquid crystal (LC) that is responsible for thestructural order observed in these substances.Typically, liquid crystal molecules consist of arigid and flexible part. The first one gives riseto the crystalline properties in a liquid crystal,while the second causes the fluidity. Themolecules of liquid crystals are usually referredto as mesogens. There are several varieties ofliquid crystals. Few of the importantclassifications are based on the shape of themolecules, orientation of the molecules, andnature of the material. Smectic LCs havemolecules that are aligned in a series of layers,with the axes of the molecules perpendicularto the plane of the layers. Nematic LCs havetheir molecules arranged in loose parallel lines.Calamitic LCs have the so called rod-likemesogens while discotic LCs have disc-likemesogens. There are also a class of LCssynthesized with bent-core or banana shapedmesogens. Thermotropic LCs exhibit phasetransition into LC as temperature changes,while lyotropic LCs phase transition is afunction of both temperature and mesogenconcentration in a solvent.
LCs are primarily known for their extensiveexploitation in electro-optical display devicessuch as watches, calculators, telephones,personal organizers, laptop computers, flatpanel television, etc. They also have diverseapplications in chromatography, spectroscopy,holography, temperature sensing, as solventsin chemical reactions and more.
The Chemistry Lab at RRI is involved in thesynthesis and characterization of a wide rangeof liquid crystals. More than 700 compoundswith bent-core or banana-shaped moleculeshave been synthesized and characterized, with
some of them exhibiting novel mesophases(the phase between crystalline and isotropicliquid) and interesting properties likespontaneous electrical polarization. The lab isequally active in the synthesis of novel disc-likemesogens that have important electronic andoptoelectronic properties. Collaborating withother members of the SCM group, theChemistry Lab often synthesizes compoundsthat exhibit specific physical properties likeferroelectric, antiferroelectric or columnarphase. Oligomeric and polymer mesogens andcompounds with novel metallo-mesogens withmagnetic properties are also investigated. Thelab is equipped with polarizing microscope,differential scanning calorimeter, digitalmicropolarimeter, infrared spectrophotometer,UV-vis spectroscopy, in addition to basicequipments required for chemical synthesis.
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PHYSICAL MEASUREMENTS
Members of the SCM group at RRI investigatephase transitions, structure, molecularorganization and physical properties ofthermotropic liquid crystals with rod-like, disc-like and bent-core banana shaped molecules.The magnetic properties of liquid crystals andtheir nanocomposites are also currently beingstudied. Nanocomposites (nanoparticles –liquid crystal composites) are another activearea of research. Dispersion of metallic,magnetic or ferroelectric nanoparticles indifferent liquid crystals is very promising fornovel future device applications. One of themajor challenge in the field is theunderstanding of the mechanisms of selfassembly of nanoparticles, so that reliablecontrol of the dispersion can be achieved withsufficient repeatability for high technologyapplications. The main advantage of LCs is theirresponsiveness to external stimuli like electricand magnetic field which provides morecontrol on the dispersion process andtunability of the nanocomposites. Currently,the SCM group is working with BaTiO3, goldnanoparticles and carbon nanotubes.
Often, novel measurement techniques aredeveloped and used to measure responses invarieties of liquid crystals with higher precisionand accuracy. Typical measurement techniquesinvolve dielectric spectroscopy, opticalbirefringence, polarizing optical microscopyand others.
LIQUID CRYSTAL DISPLAYS(LCDs)
LCD technology is the most common and widespread display technology in the world today.LCDs are literally everywhere: in our cellphones, televisions, laptop computers, videoplayers, digital watches, calculators, gamingdevices! They are much thinner, lighter,portable, less expansive, more reliable anddraw much less power compared to the oldcathode ray tubes. Research activities at RRIfocus on the development of new addressingtechniques for drive electronics in LCDs withpassive matrix, that would further reducepower dissipation and hardware complexity.RRI has patents related to its research activitiesin the field. Today, a multiline addressingtechnique, invented at RRI, is extensively usedin LCD electronics worldwide. The LCD lab hasbasic facilities to fabricate LC cells and smallsize prototype displays for testing purposes.
RHEOLOGY AND LIGHTSCATTERING STUDIES
Rheology studies the deformation and flow ofmatter when different kinds of stress areapplied to the sample. Rheology builds on topof the classical elasticity and Newtonian fluidmechanics, to extend our understanding tomaterials whose mechanical behavior cannotbe described with these classical theories. It isused to make predictions for the mechanicalbehavior of a material based on its microscopic
structure. Rheology hasimportant applications inengineering (development anduse of polymer materials),geophysics (studies of mud,snow, magma, etc) andphysiology (blood flowmeasurements).
Researchers at RRI use rheologyand light scattering techniquesto study the dynamics and
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various responses insoft glassymaterials. Examplesof these are variousconcentratedsuspensions,emulsions and gels,that are used widelyin industry. Softglassy materialsexhibit slowdynamics and serveas excellent modelsystems in theunderstanding ofnon-equilibriumglass transitions inhard condensedmatter. A mix of
synthetic clay suspended in water calledLaponite is currently a material of interest forthe SCM group. Laponite is also used to studyinstabilities at the interface that occur when alow viscosity fluid (clay) is injected into a moreviscous one (water). Such studies areimportant for various technological processeslike percolation of oil through porous rocks.
Amphiphilic compounds consist of moleculesthat have both hydrophobic and hydrophilicparts. At high enough concentrations theamphiphilic molecules start to form micelles orvesicles (amphiphilic molecules group togetherin various 3D structures arranged with theirhydrophilic part facing the solvent).Amphiphilic block copolymers are a type ofcopolymer that is used in pharmaceuticalapplications for sustained–release technologiesor gene delivery. Because of their amphiphilicnature when suspended in aqueous solutionthey start to form micelles. The hydrophobiccore of the micelles serves as a reservoir forhydrophobic drugs. Pluronic triblockcopolymer is a type of amphiphilic copolymerthat is extensively studied by researchers at RRIbecause of its enormous potential forcontrolled drug delivery applications. Rheology
techniques are used to investigate its stabilityunder stress and strain, and determine thetemperature-concentration phase diagram.Dynamic light scatterometry techniques areused to extract the particle size distribution ina sample.
ELECTROCHEMISTRY ANDSURFACE SCIENCE
The Electrochemistry and Surface Science labat RRI is actively involved in various researchactivities related to: (i) electron transferprocesses of redox molecules; (ii) electrical andphotoconductivity of doped columnar discoticliquid crystals; (iii) electrochemistry of surfacesand interfaces formed by self-assembledmonolayers and other organic thin films;(iv)electron transfer processes and conductivityin bio-molecules on electrode surfaces; (v)characterization of conducting polymernanostructures. The latter can lead to potentialapplications in sensors, energy conversiondevices and fuel cells. The lab is equipped withmodern facilities allowing for a wide range ofmeasurement techniques to be applied. Someof the extensively used equipment includeatomic force microscope, scanning tunnelingmicroscope, electrochemical quartz crystalmicrobalance, frequency response analyzerand more.
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BIOPHYSICS
The Biophysics lab was started just two yearsago. Today it’s a self-sufficient lab where cellscan be grown, manipulated and analyzed. Theprimary research focus in the Biophysics lab isthe understanding of cellular dynamics likeforce generation, movement and transportprocesses. A variety of cells is grown in the laband tested using novel experimentaltechniques. Members of the Biophysics lab arecurrently involved in the design, constructionand integration of an experimental set up thatcan provide insight into the deformations anddynamics of axons. Axons are a part of theneuron that extends from the neuron’s cellbody. In the majority of cases, they are foundto transmit electrical pulses, forming thetransmission lines of our nerve system.Experimental research of the patterning anddifferentiation of stem cells is anotherimportant activity in the Biophysics lab.
PHASE BEHAVIOR OFSURFACTANTS
Surfactants are amphiphilic organiccompounds that allow easier spreadingbetween two liquids or a liquid and solid. Theyare widely used in our everyday life asdetergents, foaming agents and emulsifiers.The research endeavor of the SCM group arefocused on fundamental understanding of thephase behavior of various surfactants withequal emphasis on interpretation ofexperimental results and development ofanalytical models.
Lipids are a group of molecules that form animportant structural component of cellmembranes. Their main biological functionincludes energy storage and “signaling”. A lipidbilayer is made up of two layers of lipidmolecules to form a continuous barrier aroundthe cell called membrane. The cell membranesof almost all living organisms and many virusesare made of lipid bilayers. Recently, a
phenomenological theory of phase transitionin lipid bilayers has been formulated byresearchers at RRI. A study of the structuralchanges induced in lipid bilayers bound totoxins and the development of a newtechnique to extract their electron densityprofiles is underway.
LIQUID CRYSTALS THEORY
Theoretical work is conducted by many of theSCM group members parallel to theirexperimental projects. Analytical models arebeing developed for the behavior of variousliquid crystals, membranes and polymers.
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CHEMISTRY LAB
Sandeep KumarSandeep KumarSandeep KumarSandeep KumarSandeep Kumar is specializing in synthesis ofliquid crystals in the Chemistry Lab at RRI. Hislast year’s individual and collaborative researchefforts have led to the synthesis andcharacterization of numerous new novelmesogens with more than a dozen paperspublished in highly reputed internationaljournals.
The synthesis and characterization of twoseries of novel triphenylene-based benzene-bridged symmetric discotic dimmers wasreported. The thermotropic liquid crystallineproperties were investigated by polarizingoptical microscopy, differential scanningcalorimetry (DSC) and X-ray diffraction (XRD)studies. DC conductivity of charge transfercomplexes at two ratios was studied as afunction of temperature. Parallel to this work,the design and synthesis of novel banana-discotic dimers and banana-bridged discoticdimers was also presented. The chemicalstructures have been characterized by spectraltechniques and elemental analysis. The thermalbehaviors of the compounds have beeninvestigated by polarizing optical microscopyand DSC. None of these synthesizedcompounds exhibited any liquid crystallineproperty probably because of theincompatibility of the bent-core with thediscotic core.
A nanophase segregated layered phase (SmA)with alternating calamitic and discotic layerswas observed for the first time in novel linkeddisc–rod oligomesogens, containing sixcyanobiphenyl moieties radially-attached to acentral tricycloquinazoline discoticheteroaromatic core via flexible alkyl spacers.
In collaboration with researchers from Malaysiaand Germany, a variety of liquid crystallinematerials having azobenzene groups wereprepared and characterized using polarizingoptical microscopy, DSC and XRD. The trans-form of azo compounds showed a strongband in the UV region (355-369 nm) and ao
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weak band in the visible region (460-470 nm).This suggested that photochromism (reversibletransformation of a chemical substancebetween two forms with different absorptionspectra by the absorption of electromagneticradiation) may be achieved by the introductionof the azo linkage in different liquid crystalsmolecules.
PHYSICAL MEASUREMENTS LAB
Arun RArun RArun RArun RArun Royoyoyoyoy is a research scientist at RRI and partof the Physical Measurements Lab. Along withPrathiba’s group, he conducted flexoelectricstudies on mixtures of compounds made ofrod-like and bent-core molecules. Theflexolectricity in nematic liquid crystals madeof bent-core (BC) molecules raised interest asthe flexoelectric coefficient of such liquidcrystals had been measured recently andindicated three orders of magnitude largervalues than that of the calamitic compounds.This large value of the flexoelectric coefficientmay lead to applications in novel sensors andmicroelectric power generators. However,most compounds made of BC molecules donot exhibit nematic phase. The flexoelectricproperties of a binary mixture of a calamiticcompound (8OCB) and a compound with BCmolecules were studied. Further details of thiswork can be found in their paper published inApplied Physics Letters this year.
Recently, BC compounds exhibiting orthogonalSmectic A phases with transversely polarizedlayers have been discovered and their potentialfor applications in new generation liquid crystaldisplays has been discussed. Experimentalstudies on a new BC compound synthesized in
Organic Chemistry Lab were carried out byArun Roy and his collaborators. This compoundexhibited two orthogonal Smectic A phaseswith decreasing temperature. Though thelower temperature phase is characterized asthe antiferroelectric Smectic A phase, thestructure of the higher temperature phase isyet to be understood. Arun Roy and hiscollaborators investigated experimentally thestructure of these phases and are currentlydeveloping a theoretical model to describe theexperimental results and the influence of anexternal electric field on the structures.
In collaboration with Soma Datta (postdoctoral fellow at RRI), Arun Roy conducteddynamic measurements of electroclinicresponse in the chiral Smectic A* liquid crystalsin the vicinity of the transition from theSmectic A* to Smectic C* phase using a newelectro-optic technique. The experimentaltechnique took into account the nonlinearityof the electroclinic response close to thetransition temperature and allowed for themeasurement of the electroclinic coefficient,relaxation frequency and the nonlinearcoefficient of the electroclinic response. It wasfound that the electroclinic coefficientdiverged with decreasing temperature as theSmectic A* to Smectic C* phase transitiontemperature was approached.
Azo functionalized materials are of specialinterest, due to their photosensitive nature,which could be exploited for optical andoptoelectronic devices. Ifsuch materials also possessliquid crystalline properties,then they have increasedpotential for technologicalapplications. Such futureopportunities have leadArun Roy and his team tothe synthesis of five newseries of azo functionalizedcompounds formed bycovalent bonding. Thestructure and
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mesomorphic properties of these compoundsrevealed that they contain both symmetric andnon-symmetric molecules and exhibit mainlynematic and columnar mesophases. Thenature of these mesophases is investigated bypolarizing optical microscopy (POM),differential scanning calorimetry (DSC) and X-ray diffraction (XRD) techniques. Preliminaryand qualitative investigation on thephotosensitivity, dielectric and opticaltransmission of the mesophases of one ofthese compounds were also carried out.
Research on dispersions of nanoparticles (NPs)of ferroelectric materials like BaTiO3 and Sn2P2S6
in liquid crystals (LCs) is being pursued veryactively by researchers from the PhysicalMeasurements Lab, because of possiblepractical applications. The stability of theseliquid crystal-nanoparticle (LC-NP) dispersionsover extended periods of time is very crucialfor the proper functioning of any practicaldevice. However, making a stable dispersion ofsuch nanoparticles in liquid crystals is acomplex process and the physical properties ofthese composite materials appear to dependon the preparation conditions. Thus, thereproducibility of the experimental data on theLC-NP dispersions is difficult and someconflicting results have been reported in theliterature. Studies were done on the stability ofthe nematic and smectic phases in the LC-NPdispersions consisting of the calamiticcompound (8OCB) doped with ferroelectricBaTiO3 nanoparticles. Different preparationconditions on making a stable dispersion offerroelectric nanoparticles in 8OCB have beeninvestigated.
The dark conglomerate (DC) phasecharacterized by a spontaneous formation ofchiral domains by achiral molecules is observedin some liquid crystals made of bent-coremolecules. Not many physical studies of thisintriguing phase are yet available. R PratibhaR PratibhaR PratibhaR PratibhaR Pratibhaand her colleagues are now involved in adetailed investigation of the dielectricproperties of bent-core liquid crystals that
exhibit DC phase and a glass transition at lowertemperatures. The technique used by thegroup is dielectric spectroscopy. The specimenwas synthesized recently in the OrganicChemistry Lab.
Last year Pratibha’s PhD students, guided bytheir advisor, conducted experiments to studythe macroscopic orientational order in a binarymixture composed of rod-like and bent-coremolecules. Optical birefringencemeasurements in a rod-like (R) compound andits mixtures with a compound made of bent-core (BC) molecules were carried out. Infrared
dichroism technique was used to analyze oneof the mixtures.
Pratibha is collaborating with researchers fromUniversity of Colorado, Boulder, CO, USA in theinvestigation and further understanding oftunable optical metamaterials. Metamaterialscomposed of plasmonic metal nanoparticlesand liquid crystals (LCs) have a high potentialto form tunable optical metamaterials.Plasmonic metal nanoparticles exhibitrefractive index tenability while the propertiesof liquid crystals can be tuned by the action ofexternal fields. Such metamaterials have theadvantage that their mass production is muchfaster and cost effective compared to thoseformed by nano lithographic techniques.However one of the major challenges is toobtain good dispersion of the NPs in the liquidcrystal matrix. Their previous work on
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dispersionsof goldnanospheres(GNS) insmecticliquidcrystals hasshown thatnot only is itpossible to form stable uniform LC-GNSdispersions without any aggregation of theGNSs but it is also possible to tune the opticalproperties as a function of the volume fractionof the GNSs. To facilitate further thecomposition of such metamaterial, it is offundamental interest and importance tounderstand what are the reasons for theenhanced stability of the GNSs in layeredsmectic liquid crystals. Last year, the teammade a careful analysis of a set of AFM datawhich revealed smectic layer deformationprofiles caused by the GNSs in thin films of theLC-GNS dispersions. The study alsodemonstrated that spatial structuring of thenanoparticles can be used as a tunableparameter in LC-GNS dispersions.
D VD VD VD VD Vijayaranghavan ijayaranghavan ijayaranghavan ijayaranghavan ijayaranghavan is a scientific officer in theSCM group. His research interests lie in the fieldof nanoparticle-liquid crystal composites, theirphysical and in particular their magneticproperties. During the year, he concentratedhis efforts on studying the physical propertiesof liquid crystal-nanoparticle composites,diamagnetic properties of lyotropic liquidcrystals and high magnetic field experiments.The first theme involved magneticsusceptibility, optical birefringence andelectrical conductivity studies of a nematicliquid crystal doped with differentconcentrations of carbon nanontubes. Thesamples were provided by Kumar from theOrganic Chemistry Lab. It is known thatnematic liquid crystals (LC) can be used asaligning agents for single walled carbonnanotubes (SWCNTs) and the presence ofSWCNTs, in return, increases the nematicordering of the liquid crystalline molecules. The
birefringenceanddiamagneticanisotropywere studiedas a functionoftemperature(the
temperature range was chosen around thenematic-isotropic (NI) transition). CNT bundleswere found to increase with increasedconcentration of SWCNTs. Polarized opticalmicroscope (POM) studies on these compositesto look for the alignment of CNT bundles nearNI transition temperatures are in progress.
Very few direct measurements of magneticsusceptibility in the surfactant based lyotropicliquid crystals (LLC) have been reported. In2005, Vijayaranghavan carried out a directmeasurement of diamagnetic susceptibilityusing a Faraday balance on an ionic surfactantbased LLC. Systematic susceptibility studieswere done on the system using SAXS and/orLight Scattering technique. The results revealeda correlation between the micellar sizes andshapes to the susceptibility. The diamagneticanisotropy behavior in the nematic phase wasalso analyzed.
LIQUID CRYSTAL DISPLAY LAB
T N RuckmongathanT N RuckmongathanT N RuckmongathanT N RuckmongathanT N Ruckmongathan runs the Liquid CrystalDisplay Lab where his group is concentrated onthe development of new addressingtechniques to reduce power dissipation andhardware complexity of drive electronics inpassive matrix LCDs. An application for anIndian patent related to bit-slice addressingand local switching of backlight techniques wassent in January 2010. Most LCDs use backlightand much power is wasted illuminating thedark pixels. The bit-slice addressing is a serialapproach to driving LCDs, that combinesintensity modulation backlight for each bit ofgrey to reduce hardware complexity. The DAC
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in LCDs can be replaced with voltage levelshifters to switch pixels ON or OFF dependingon the gray shade bit to further reduce thehardware complexity of data drivers. About80 to 90% of power is consumed by thebacklight in LCDs. A maximum of 40% and anaverage of 26% reduction in powerconsumption of backlight was achieved for 27standard images used for image processing byswitching OFF backlight illumination whenevergrey shade bit was zero for all pixels in acluster of 256 (16 x 16) pixels.
Ruckmongathan is also exploring the possibilityfor applying compressive sensing to displays.The motivation for this work is the ‘single pixelcamera’ that uses optical mask and a photodetector for compressive sensing. Display isthe inverse process of sensing; as such there isno breakthrough till today.
X-RAY DIFFRACTION LAB
V A RV A RV A RV A RV A Raghunathanaghunathanaghunathanaghunathanaghunathan is the head of the X-ray Labwithin the Soft Condensed Matter Group. Heconducts fundamental research in the area ofphase behavior of surfactants using boththeory and experimental results for hisinterpretations. Last year, a collaborative workwith his PhD student Arif Kamal and MadanRao led to the development of aphenomenological theory of phase transitionsin lipid bilayers. Many lipids of biological originself-assemble in water to form lamellar phases
consisting of a periodic stack of bilayersseparated by water. Different lamellar phaseswere observed as a function of temperature.Although there have been quite a fewattempts at formulating a phenomenologicaltheory of transitions between these phases,none of them is able to explain all theirexperimentally observed features. The theorydeveloped by the group was able to accountfor all the salient structural features of thesephases.
Many toxins, such as cholera and shiga toxingain entry into the host cell by inducingtubulation of the plasma membrane.Experiments using model membranes showthat such tubulation occurs only with certainclass of lipids. This lipid specificity is currentlynot understood. A systematic study ofstructural changes induced in lipid bilayers bybound toxins has been initiated byRaghunathan in collaboration with researchersfrom Curie Institute, Paris, France. In the firststage of this study, both cholera and shigatoxins were found to increase the lamellarperiodicity of the lipid bilayers on binding. Theconditions under which non-lamellar structureswould be stabilized in these systems is beingcurrently probed. Such non-lamellar structureswould play an important role in the tubulationof the plasma membrane.
Amphiphilic molecules self-assemble in waterto form aggregates of various morphologies,
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such as spheres, cylinders and bilayers. Inaddition to these well-known morphologies,some of these systems also form a network ofcylinders over narrow regions of the phasediagram. Raghunathan’s group has recentlyfound some surfactant-water systems wherethese catenoid phases occur over a wide rangeof composition. Further, temperature driventransitions between catenoid phases ofdifferent symmetries have also been observedfor the first time. Experiments are underway tounderstand the role of different structuralparameters of the surfactant in stabilizingthese phases. A phenomenological model forphase transitions in these systems is also beingdeveloped.
The electron density profiles (EDP) of lipidbilayers may be calculated from X-raydiffraction data using Fourier reconstructiontechniques. A few methods have beenreported in the literature to determine the EDP.While calculating the EDPs of some lipid
mixtures, Raghunathan and his colleagueGeorg Pabst at the Institute of Biophysics andNanosystems Research, Austria, realized thatthese methods give inconsistent results. A newmethod has been proposed which avoidsthese drawbacks and can also be extended todetermine the composition of lipid mixtures.
Many surfactants form highly swollen andstable lamellar phases in water. In some of
these systems the lamellar periodicity iscomparable to the wavelength of visible lightand hence they display iridescence. Suchsystems have been of interest to both – thecosmetic industry and Raghunathan. Whilestudying the stability of a swollen lamellarphase of the ionic surfactant alkenylsuccinicacid (ASA), it was found that small amounts ofa non-ionic surfactant could lead to thecollapse of this phase. Bridging interactionsbetween the bilayers, arising from hydrogenbonding of the polymer to the acid headgroupof ASA is responsible for the collapse. Similarmechanisms could be involved in fusion of lipidvesicles, where the apposing membranes haveto be brought into close proximity for fusionto occur.
BIOPHYSICS LAB
One of the major research efforts of PramodPramodPramodPramodPramodPullarkat’sPullarkat’sPullarkat’sPullarkat’sPullarkat’s group is probing the mechanicalproperties of axons. Their partners includeresearchers from University of Santiago,Chileand Indian Institute of Science Education andResearch (IISER) , Pune, India. F. Melo, R. Bernaland P. Pullarkat developed a new flow-technique for probing the mechanicalproperties of Axons. A related paper has nowbeen reviewed and published. A system whichuses a novel optical fiber based forcemeasurement technique to probe axonalmechanics was assembled last year. Thenecessary software to track the position of thefiber with a very high accuracy was developedin-house. Another code was written in order tointerface the detectors and actuators. ChiragKalelkar, a visiting post doctoral fellow,calibrated a camera and a Position SensitiveDetector (PSD). Currently, the piezoelectricactuator is being integrated into the system,after which the set up will be ready forpreliminary experiments.
Axon instabilities are also actively studied bylooking at the mechanism behind theformation of roughly periodic swellings in
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axons under inducedneurodegenerativeconditions. Atechnique tofluorescently label thevarious cellularcomponents ofinterest wasdeveloped. A new flow-chamber has beenconstructed, and tested. A huge amount ofeffort was put into improving the cell culturetechniques in order to obtain goodquantitative data. Preliminary experimentsusing various biochemical agents againstspecific axonal components have beenperformed. Reliable quantitative data areexpected in the next six months.
Another major project of Pullarkat and histeam aims at investigating stem celldifferentiation in externally imposed chemicaland substrate stiffness gradients. The idea is tomimic and study pattern formation indeveloping embryos using stem cells. A microfluidic system to sustain concentrationgradients was developed and cell viability insuch conditions was verified. Thin (100—500microns) sheets of gels with varying stiffnessare being prepared and their Young’s modulimeasured. Current activities involve developingstiffness gradients and looking at cellresponses in stiffness/chemical gradients.
ELECROCHEMISTRY & SURFACESCIENCE LAB
V LV LV LV LV Lakshimnarayanan’sakshimnarayanan’sakshimnarayanan’sakshimnarayanan’sakshimnarayanan’s time at work is spentmostly in the Electrochemistry and SurfaceScience Lab. Significant time and effort of hisgroup last year went into the electrochemicalsynthesis of the so called “metalnanoparticles impregnated conductingpolymer films”. Metal nanoparticles such asPalladium and gold dispersed in conductingpolymers possess excellent electrocatalyticproperties, which find potential applications insensors, energy conversion devices and fuel
cells. A singlestepelectrochemicalmethod wasdeveloped toprepare Pdnanoparticlesdispersed in the
conducting polymers. The methodsimultaneously produced conducting polymerstabilized metal nanoparticles in solution aswell as a thin film of the nanocomposite on thesurface. The electrocatalytic effect of thesenanocomposites have been demonstrated formethanol, ethanol and formic acid electro-oxidation which are the essential anodicreactions in the low temperature direct fuelcells. Due to the excellent hydrogen evolutionproperty of the dispersed Pd nanoparticles,this material has the potential to emerge as analternative to the more expensive platinum forhydrogen generation by electrolysis. Theresearch involved extensive characterizationusing techniques like Atomic Force Microscopy(AFM), FTIR, surface XRD, XPS andelectrochemical studies. For practicalapplications in fuel cells, the nanocompositefilm needs to be coated on a graphitesubstrate, which is less expensive andpreferred substrate material. Theelectrocatalytic effect on alcohol oxidation inacidic as well as alkaline media for thesecoatings on graphite substrate wasinvestigated. The studies showed that the film
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coated on graphite can also be effective ascatalyst material for fuel cell applications.
Using a simple one –step electrochemicalprocess, it is possible to form a thin film ofgold nanoparticles on metal surfacespossessing very high electrocatalytic activityfor alcohol oxidation in alkaline media. Dueto its nano scale geometry, the Aunanoparticles coated surfaces are expected tobehave differently for the study of electrontransfer processes when compared to thenormal planar electrodes. Lakshminarayanan’sgroup examined the behaviour of classicalreversible redox systems on a surface coatedwith Au nanoparticles and demonstrated thepotential of such a surface as a bio-sensor forglucose and dopamine which is an importantneurotransmitter.
One of the areas of intense research in softcondensed matter is the study of electricalconductivity of biomolecules such as DNA andproteins. In this regard, Lakshminarayananlooked at STM images for the redox proteinssuch a cytochrome-c and myoglobin whenimmobilized on gold surface. The surfacefeatures were of several tens of nanometerswhich clearly pointed to the possibility ofelectron tunneling through the proteinmolecules. This prompted a study of theelectrical conductivity of the redox proteincytochrome-c. The current – voltagecharacteristic was measured using scanningprobe microscopy. The results obtainedconfirmed the electrical conductivity of hemeproteins and further work is under way tounderstand this mechanism.
Study of Photoconductivity of Discoticand Doped Discotic Liquid Crystals is ajoint effort between Lakshminarayanan,Kumar and G Kavitha. Polymer organicphotoconductors have been used asphotoconductive media in the field ofxerography and laser printing. Theefficiency of photocopier and laserprinters is due to the mobility of chargecarriers in the photoconductive layer,
therefore a lot of effort goes into thedevelopment of such organicphotoconductors. Currently, the focus is ondesigning an instrument to measure thephotoconductivity of liquid crystals. Directphotocurrent measurement as a function oftemperature was set up and fruitful results ofthe dark conductivity and photoconductivity ofpure as well as doped triphenylene wereobtained. Such materials can also findpotential application in organic thin film solarcells. This work is in a preliminary stage and isexpected to provide some new excitingfindings in the near future.
RHEOLOGY AND LIGHTSCATTERING LAB
RRRRRanjini Bandyopadhyayanjini Bandyopadhyayanjini Bandyopadhyayanjini Bandyopadhyayanjini Bandyopadhyay is a research facultymember of the SCM Group and the head ofthe Rheology and Light Scattering Lab. Herresearch group employs dynamic lightscattering, rheology, optical imaging or acombination of these techniques to study thestructures, dynamics, stability and mechanicalresponses of a diverse range of soft materials.In a recent paper published online in SoftMatter, she discussed the stress relaxation ofaging colloidal glasses. Concentratedsuspensions, emulsions and gels exhibit richphysical behavior and are widely used in theindustry. Generically, these materials,characterized by slow dynamics, are classifiedas soft glassy materials. The motivation for thiswork came from the fact that these soft glassymaterials serve as excellent model systems inthe understanding of the non-equilibrium glass
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transition in hard condensed matter systems.The relaxation phenomena of such systemswere studied by analyzing the temporalbehavior of the response functions to anapplied step strain. The results demonstratedthat this method is an excellent alternative tolight scattering experiments in understandingthe relaxational dynamics of soft glassymaterials.
Pluronic block copolymer micelles have anenormous potential as drug delivery agents.The association of additives with Pluronicmacromolecules is therefore a very interestingtopic and recent experiments have studied theaggregation of Pluronic micelles in thepresence of the drug Ibuprofen. In particular,an understanding of the interaction betweencopolymers and surfactants is important dueto the wide use of polymer-surfactantmixtures in the manufacture of paints,detergents, cosmetics and pharmaceuticals.Using dynamic light scattering and rheometry,Bandyopadhyay investigated the changes inthe mechanical moduli of a Pluronic solutionon the addition of the anionic surfactant. Theresults are to be published in a peer-reviewedjournal soon. The group’s future intentions areto explore the potential of Pluronic as a drugdelivery agent.
When a low viscosity fluid is injected into amore viscous fluid, (as in injecting water inglycerine), an instability called the SaffmannTaylor instability is created. The understandingof this instability is important because of theubiquity of such processes in technologicalapplications, such as the percolation of oil inporous rocks. Bandyopadhyay has started aproject the main purpose of which is toinvestigate the physics behind the patternformation at the quasi-two dimensionalinterface between a Newtonian fluid (water),and an aging non-Newtonian fluid (an aqueoussuspension of the synthetic clay, Laponite).The role of the rate of injection of water intothe cell containing the Laponite on thepatterns formed will be investigated. The
standard tools of fluid mechanics will be usedto understand the transition between theSaffmann Taylor and the crack propagationregimes.
While the structural differences between a geland a glass are well known, the aim of anotherof Bandyopadhyay’s projects is to identify thedifferences in the rheology exhibited by thegel and the soft glassy phases. In synthetic claysamples of Laponite or Bentonite, softrepulsive glasses form above a critical clayconcentration under very low or no saltconditions. Gels, which can be thought of astenuous interconnected networks, form whenthe repulsion between individual particles isscreened by adding salt. Having establishedthe presence of soft glassy rheology inLaponite suspensions, extensive experimentswere performed on Laponite and Bentonite
suspensions over a range of clayconcentrations with and without added salt(NaCl). From the microscopy data, it isexpected that an NaCl vs. Bentoniteconcentration phase diagram could also beconstructed over a wide range of Bentoniteand NaCl concentrations.
Bandyopadhyay’s other interests this yearinclude the rheology of concentratedcornstarch suspensions, light scattering frompolystyrene beads dispersed in aging Laponitesuspensions (done in collaboration withresearchers from the Theoretical Physics Group
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at RRI) and the effects of base roughness onthe motion of vibrated granular beads.
THEORY OF LIQUID CRYSTALS
YYYYYashodhan Hatwalneashodhan Hatwalneashodhan Hatwalneashodhan Hatwalneashodhan Hatwalne conducts research in thewide field of soft matter physics. His work thisyear was both analytical as well asexperimental in nature. A recent paper waspublished describing the laser induced rotationof trapped chiral and achiral nematic droplets.Manipulation of suspended micron- sized fluiddroplets by light is interesting for fundamentalreasons as well as for applications such asoptical switches. Chiralised as well as achiralnematic droplets suspended in water and inglycerol solution were manipulated with lasers.It was found that chiralised nematic dropletscan be set into rotation using plane polarisedlight. The difference in the law followed by therotation frequency of droplets suspended inglycerol solution (more viscous than thenematic material) and those suspended inwater showed the importance of internaldissipation in the droplets.
Another of his experimental projects includedthe study of growth morphologies in giantunilamellar vesicles (GUVs). GUVs areextensively studied and used in soft matterphysics and biological physics. The mostpopular method of producing them is the socalled “electro-formation method”, in whichplatinum wires coated with surfactants arehydrated under an alternating electric field. Atthe present time the mechanism which leads
to the formation of GUVs is not understood,and the method is a mere recipe. Hatwalne’sgroup was motivated to make a headway inunderstanding this mechanism. They foundthat the first step in the electro-formationprocess (hydration of the dried surfactant on aplatinum wire, or a cover slip) is in itself verycomplex, exhibiting some previously unknowninstabilities. The process of hydration lead tovery interesting structures that wereextensively studied using various microscopictechniques. An attempt was made to describethese observations using a qualitative theorythat exploited the interplay between elasticity,topological defects, and flow.
On the theoretical front, Hatwalne was lookingat the morphologies of polymer crystallites.Solution- grown or melt- grown polymercrystallites show fascinating morphologies.These structures have been observed since1952, but there is no quantitative theory whichadequately describes them. Hatwalne and hiscollaborators - Jaya Kumar and M.Muthukumar, formulated a phenomenologicaltheory to explain the observed morphologies.The theory makes some interesting predictionsthat could be tested experimentally, and is thefirst complete theory which accounts for theentire range of observed morphologies.
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TheoreticalPhysics
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TheoreticalPhysics
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Established around 1995, the TheoreticalPhysics (TP) group is a vibrant community ofresearch faculty, post doctoral fellows andstudents that work at the interface betweenmathematics and physics. There are two maindistinct areas of research – gravity andstatistical mechanics. Individual members’interest within the area of statistical mechanicsbranch into mesoscopic physics, nonequilibrium physics, soft condensed matterphysics and biophysics. Research in generalrelativity includes gravitational waves andquantum gravity. Members often engage incollaborations among each other and/orgroups of the institute that conductexperimental physics activities. The group hasalso created a forum for theorists to “dirty”their hands with simple table-top experimentsthat can express conceptual points.
The following pages summarize the majorareas of research for the TP group. Eachmember’s individual work during the last yearis provided in the next section, giving thereader more detailed and technical descriptionof their respective research activities.
STATISTICAL MECHANICS
When a macroscopic device or a sample ofbulk material are scaled down to mesoscopicsize (from few microns to the size of a singleatom), they begin to reveal quantummechanical effects. As a result, their propertiesmight be very different from the ones of theirbulk counterparts.
Research at RRI is focused on thedevelopment of a theory of heat and electrontransport in such mesoscopic scale systems.Part of that work includes analytical andnumerical treatment of the Fourier’s law ofheat conduction in disordered harmonic andanharmonic crystals. Theoretical andexperimental research in that field is importantfor the advancement of our fundamentalunderstanding of the transport properties ofmaterials, which in turn would lay theo
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foundation needed for improving theperformance of nanodevice applications andtechnologies.
The development of fast algorithms forestimation of the probability of rare events ispart of the ongoing research in the field of nonequilibrium statistical mechanics. Developed inthe context of physics, such algorithms are alsoimportant in other areas like finance and cellularprocesses in biology.
BIOLOGICAL PHYSICS
Various topics in the field of biophysics haveattracted the interest of the TP group. Hereagain is an example of the value of having arelatively small institute with a wide range ofprofessional research interests and scientistswho are open-minded, and eager to move intonew areas and apply their experience torelated fields. Current activities in biophysics atRRI are focused on mitochondrial distributiondynamics, vesicle formation and thedevelopment of analytical models to describeDNA elasticity (stretching, twisting and variousdeformations). Membranes, and transport ofmaterials in the cell are other topics which hasbeen pursued at RRI. Research in this areainvolves active collaboration with experimentalgroups in NCBS (National Center for BiologicalSciences) and on campus.
GRAVITATIONAL WAVES
The existence of gravitational waves waspredicted by Albert Einstein’s theory of generalrelativity in 1916. Their existence is inferredusing indirect methods but they have not beenmeasured directly yet. The direct detection ofsuch waves will help scientists test generalrelativity more thoroughly. More importantly, itwill open a new “eye”, with which we mayobserve objects and phenomena in theUniverse that stay invisible for the optical andradio astronomy.
In general, sources of gravitational waves arebodies with strong time dependentgravitational field. These include binary starsystems composed of white dwarfs, neutronstars or black holes. The orbiting bodies ofsuch systems continually lose energy whileradiating gravitational waves. This leads todecrease in the distance between the bodiesforcing them to rotate more rapidly, thusincreasing their loss of energy to gravitationalradiation. For systems like the Sun-Earth onemay find this effect to be negligible on thetime scales of the Universe. The closer thebodies in the binary system, the larger thiseffect is, leading eventually to a collision thatcan result in a merger or the creation of ablack hole. Such binaries are referred to asinspiralling binaries because the bodies in thebinary system describe a spiral as theyapproach each other.
LIGO stands for Laser InterferometerGravitational-wave Observatory and is a jointscientific experimental project attempting todetect directly gravitational waves. The projectis led by scientists and engineers from MIT,Caltech and other universities. VIRGO is anotherinterferometer aiming at direct gravitationalwave detection which is a result of the effortof various European institutions. Both theseinstruments are built and tested and haveachieved their design sensitivities. The signalsexpected are extremely weak and buried innoise. A major challenge now is the accuratecalculation of the expected gravitationalwaveforms from the observed binary systems.Later, these waveforms are cross-correlatedwith the observational data in order to extractthe gravitational wave signature. Researchersat RRI are currently looking at ways to preciselycalculate the gravitational waveform from fewinspiralling binaries. In future, these areexpected to improve the sensitivity of otherenvisioned space instruments aiming atdetecting gravitational waves like LISA (LaserInterferometer Space Antenna).
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QUANTUM GRAVITY
At present, the formulation of a theory ofquantum gravity engages and challenges theminds and creativity of many scientists in thetheoretical physics community. Quantumgravity (QG) is envisioned to be a selfconsistent theory that will quantize the gravityfield thus combining the two major theories ofquantum mechanics and general relativity.There are a handful of QG theories beingdeveloped in parallel like the string theory,loop quantum gravity or causal set theory.Research at RRI is focused on the last twoapproaches to quantum gravity.
Loop Quantum theory proposes that all thespace where physical phenomena happen berepresented by continuity of finite quantizedloops of excited gravitational fields called spinnetworks. Unlike string theory, loop quantumgravity (LQG) doesn’t try to unify all four majorforces (electromagnetic, gravitational, strongnuclear and weak nuclear force). The majorchallenge for LQG comes from the fact thatquantum theory relies on a reference(background) space-time, while generalrelativity is said to be backgroundindependent. The approach of LQG is toformulate quantum mechanics without relyingon the space-time reference. Members of theTheoretical Physics group at RRI develop newmathematical tools and ideas as steps towardsthe development of a true theory of quantumgravity.
Causal Set theory is another approach toquantum gravity. Its founding principle statesthat space-time is fundamentally discrete andthe relations between space-time events arecausal. Members at RRI with a focus of thecausal set theory investigate classical stochasticgrowth modes, topology and dynamics of thecausal set in their attempt to construct aconsistent quantum theory of causal sets.Parallel to that, investigations of the observer-independent alternative formulation ofquantum theory are currently beingconducted.
In his early days, Einstein believed that theUniverse was static. His general relativity theorywas predicting otherwise, so he added a termcalled the cosmological constant that madethe Universe static. Later on, Hubble providedobservational proof that the Universe wasexpanding and Einstein abandoned thecosmological constant calling it the “biggestblunder” in his career. Recently, the interest inthe cosmological constant amongcosmologists and theoretical physicists hasincreased mainly because its inclusion as acosmological parameter significantly improvesthe agreement between theory andobservation.
The gravitational pull of matter is expected toslow down the expansion of the universe.Surprisingly, observations of supernovaeindicate that the universe expansion isaccelerating! Such results, though preliminaryin nature, raise the possibility that the universecontains an unknown form of matter orenergy that is gravitationally repulsive. Thecosmological constant may describe suchmatter or energy, but a lot more work remainsbefore cosmologists and theoretical physicistscan throw light on this mystery! Anotherreason for the reintroduction of thecosmological constant is that the estimatedage of the universe (with the amount ofmatter we observe) by cosmological modelsthat don’t take it into account is less than theage of the oldest stars we observe. When thecosmological constant term is added to thestandard theory of Big Bang it becomesconsistent with various astronomicalobservations. Building on the work of Sorkin,who suggested that the observed cosmologicalconstant may be due to quantum gravityfluctuations, researchers at RRI pursue ananalogy between that elusive term in thetheory of general relativity and the surfacetension of fluid membranes. This is yet anotherexample of the collaborations that emerge atthe Institute due to the interactions betweenmembers with different fields of research.
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STATISTICAL MECHANICS
Abhishek DharAbhishek DharAbhishek DharAbhishek DharAbhishek Dhar conducts active research inthe field of statistical mechanics and softmatter physics focusing mainly on thedevelopment of a microscopic theory ofheat and electron transport. Collaboratingwith Dibyendu Roy and scientists from IISc,he studied mesoscopic systems trying tounderstand electron transport across smalldevices such as quantum dots in situationswhere the interactions between electronsare strong. For a simple model of spinlessinteracting fermions, two new phenomena- a two-particle resonance effect anddiode-like behavior were investigated.
Fourier’s law of heat conduction is aphenomenological law and it does nothave a rigorous microscopic derivation.Last year, Dhar worked along withresearchers from USA, Germany and Japanon the open problem of finding what werethe necessary conditions under whichFourier’s law was valid in three-dimensional systems. In crystalline solids,lattice vibrations (phonons) are thecarriers of heat and two importantmechanisms for scattering of the phonons– anharmonicity and disorder were studiedto find out if they can lead to a finite heatconductivity of the crystal. In the case ofheat conduction in disordered harmoniccrystals, the system size dependence ofthermal conductivity was addressed andanalytic results obtained. These resultswere then tested through extensivenumerical calculations and simulations. Aconflict between the two currently poses achallenge before the group. In the case ofheat conduction in anharmonic crystals,nonequilibrium simulations in a threedimensional anharmonic lattice weredone. The results confirmed the threedimensional system had finite thermalconductivity thus providing the firstverification of Fourier’s law.o
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The risinginterest ineverything“nano” hasbrought theneed tounderstandand measurethe heattransport inlow-dimensionalsystems such asnanowires,nanotubes and
graphene. Some interesting data on thermalconductivity in n-type In-As nanowires wererecently obtained by a group in TIFR. Resultsshowed that the thermal conductivity wasabout 1000 times smaller than bulk sampleswhile the electrical conductivity was almostunaffected. Also, the applied gate voltageswere found to have a strong effect on thethermal conductivity. Dhar is part of a teamworking towards thorough interpretation ofthese results.
Sanjib SabhapanditSanjib SabhapanditSanjib SabhapanditSanjib SabhapanditSanjib Sabhapandit focused his research lastyear on the development of an algorithm forfinding probabilities of rare events and itsapplication to non-equilibrium processes. Heand Dhar tested the algorithm on steady stateparticle and heat transport in model systems.The algorithm performance was significantly
faster compared to other direct simulationmethods.
Samarth ChandraSamarth ChandraSamarth ChandraSamarth ChandraSamarth Chandra joined the institute as a postdoctoral fellow in November 2009. His areas ofcurrent professional research interests arestatistical mechanics and biophysics. Sincebecoming a member of the Theoretical PhysicsGroup at RRI, he has developed an algorithmfor finding approximate ground states of aspin glass of classical continuous spins whichare much closer to experimental reality thanthe Ising spin case. This algorithm isindependent of the dimensionality of thelattice. In the future he plans to implement thisalgorithm to study the properties of spin glassground states for three or higher dimensionallattices. Samarth has also formulated amethod for constructing classical spin modelsfor given states as ground states. Future workincludes studying of these models withinteresting, non-trivial ground states wheresome novel low temperature behavior isexpected.
BIOLOGICAL & SOFTCONDENSED MATTER PHYSICS
Joseph SamuelJoseph SamuelJoseph SamuelJoseph SamuelJoseph Samuel is a mathematical physicistwho works in the fields of general relativity,optics and soft condensed matter physics. Heuses geometry and topology to describephysical phenomena and this thread tiestogether his diverse fields of research. One ofhis main interests last year was in the elasticityand statistical mechanics of DNA. There aresingle molecule experiments which probe theelastic properties of DNA by pulling andtwisting them. The interpretation of theseexperiments requires special attention becauseof the geometric and topological subtleties ofthe writhe in the DNA. In collaboration withSupurna Sinha, he is working towards solvingsimple theoretical models and extracting theirexperimental predictions.
The team of Samuel, Sinha and KattiSamuel, Sinha and KattiSamuel, Sinha and KattiSamuel, Sinha and KattiSamuel, Sinha and Katti pursuedthe analogy between the cosmological
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constant of the Universe and the surfacetension of fluid membranes. The analogydeveloped earlier was refined by computersimulations which showed that the surfacetension of a fluid membrane has statisticalfluctuations stemming from its discretemolecular structure. According to them, thisimplies that a fluctuating cosmologicalconstant is a generic feature of quantumgravity models and goes beyond the specificcontext in which it was originally proposed.This work is interdisciplinary in nature and triesto understand abstruse quantum gravityeffects in using simpler systems which arebetter understood.
Supurna SinhaSupurna SinhaSupurna SinhaSupurna SinhaSupurna Sinha is a research faculty member ofthe TP Group whose major research interestsare focused in the field of statistical mechanicsand its applications. In collaboration withJoseph Samuel and Poonam Mehta she putforward the proposal of a polarizedinterferometer experiment which measuresthe nonlocal Pancharatnam phase acquired bya pair of Hanbury Brown-Twiss photons. Theexperimental setup involves two polarizedthermal sources illuminating two polarizeddetectors. Varying the relative polarizationangle of the detectors introduces a geometric
phase equal to half the solid angle traced outon the Poincare sphere by a pair of photons.Local measurements at either detector do notreveal the effects of the phase, which appearsonly in the coincidence counts of the twodetectors and is a genuinely multiparticle andnonlocal effect. The phase is an optical analogof the multi-particle Aharonov-Bohm effectwhich has been measured in Quantum Hallsystems.
NarNarNarNarNarendra Kumarendra Kumarendra Kumarendra Kumarendra Kumar is a Homi BhabhaDistinguished Professor at RRI whose researchinterests are generally in randomness,dissipation, and decoherence in condensedmatter. Last year, he tackled the problem oflight transmission through a slow wavemedium. Wave compression, amplification,energy storage and its delayed transmissionthrough a low wave medium was studiedanalytically based entirely on the continuityequation for the optical energy flux. Resultsprovided a phenomenological understandingof some recent experiments on light storageand its delayed transmission through amagnetically tunable ferrofluidic medium.
Madan RMadan RMadan RMadan RMadan Rao’s ao’s ao’s ao’s ao’s research is focussed on drivencollective phenomena in materials and the cell.His research deals with descriptions of thedynamics and steady states of systems drivenfar from equilibrium, especially in the contextof solids, soft materials and cells and tissues.In the context of driven solids, Rao and Surajit
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Sengupta from IACS, Kolkata have beenworking on understanding the properties ofsolids driven as a result of structuraltransformation and/or external stresses. Thestudy has revealed unusual connectionsbetween the physics of such systems andglasses and granular media.
One other major subject of study is theelucidation of theoretical approaches in cellbiology, specifically in the physics of active,evolving systems, i.e., systems comprisingmolecular processes fuelled by a steadythroughput of energy. The main interest is inthe organization, flow and processing ofchemical composition, mechanical stress,energy and information in living cells andtissues. These new physical principles are aconsequence of the novel response of cellularsystems to local active forces which maintain itaway from equilibrium. These active forcesarising from (i) the coupled dynamics of thecytoskeleton, motors and cytoskeletalregulatory proteins, and (ii) the active
dynamics of fission and fusion of organelles,regulate the flux of composition, momentum,energy and information.Rao has beenengaged in developing a theoreticalframework, called active hydrodynamics, toaddress the relationship between fluxes andforces in a variety of contexts, where activityplays a significant role. Using this frameworkRao along with other collaborators from RRI,NCBS and IISc. have studied the mechanicalresponse, pattern formation, symmetrybreaking and hydrodynamic instabilities in bothin-vivo and in-vitro reconstituted activesystems.
GENERAL RELATIVITY &QUANTUM GRAVITY
Bala IyerBala IyerBala IyerBala IyerBala Iyer conducts mainly theoretical researchin the field of general relativity andgravitational waves. His last year’s researchincluded parameterized tests of post-Newtonian theory using Advanced LIGO andEinstein Telescope. General relativity has veryspecific predictions for the gravitationalwaveforms from inspiralling compact binariesobtained using the post-Newtonian (PN)approximation. Measurement of the PNcoefficients is possible with the secondgeneration gravitational wave detectors suchas the Advanced LIGO, and the third generationgravitational-wave detectors such as theEinstein Telescope (ET). The extent to whichsuch measurements could be used to testpost-Newtonian theory and put bounds on aclass of theories which differ from generalrelativity was investigated. This work was donein collaboration with Chandrakanth Mishra andresearchers from Washington University, St.Louis, and Cardiff University.
Recent breakthroughs in numerical relativityenable one to examine the validity of thepost-Newtonian expansion in the late stages ofbinary inspiral. Previous work on factorized re-summed waveforms by Damour, Iyer andNagar showed that they achieved better
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agreementwithnumericalresults thantheconventionalTaylorexpandedpost-Newtonian waveforms. Iyer and RyuichiFujita (currently a post doctoral fellow at RRI)revisited and refined that work. Theimplications for the construction of waveformsfor prototypical compact binary sources indetectors like LISA were examined.
Fruitful collaboration between Iyer, scientistsfrom University of Maryland and CardiffUniversity investigated the (dis)agreementbetween different PN waveform families in thecontext of initial and advanced gravitational-wave detectors. For their study they usedwaveforms employed currently by Initial LIGO/Virgo project. The orbital evolution of aninspiralling compact binary cannot be specifieduniquely due to the inherent freedom in thechoice of parameters used in the PN expansionand the method used in solving the relevantdifferential equations. The group tried toquantify the differences in few time domainPN models and decide whether there existpreferred families of search templates in termsof detection ability and computational cost.
Iyer’s last year’s research also includesinvestigation of head-on collision of twocompact objects with arbitrary mass ratios(using the multipolar post-Minkowskianapproximation method) and the computationof the angular momentum flux from aninspiralling binary system of compact objectsmoving in quasi-elliptical orbits. Both studiesare essentially important for the comparison ofpost-Newtonian results with the numericalrelativity simulations.
Madhavan VaradarajanMadhavan VaradarajanMadhavan VaradarajanMadhavan VaradarajanMadhavan Varadarajan works in the field ofclassical and quantum gravity. Building on aprevious work, he and Alok Laddha (a postdoctoral fellow ar RRI), carefully analyzed the
quantumdynamics in theLoop QuantumGravity (LQG)model, andargued that thedefinition ofquantum
dynamics in the model missed importantsubtleties. Their work was a strong indicationthat the definition of the magnetic fieldoperator in LQG must be sensitive to the(conjugate) electric flux carried by the LQGquantum (spin network) states.
Currently, Varadarajan is working on the hardproblem of defining quantum dynamics inLQG and the black hole information lossproblem. The latter is being studied incollaboration with A. Ashtekar from Penn StateUniversity and V. Taveras from Luisiana StateUniversity.
Sumati Surya’sSumati Surya’sSumati Surya’sSumati Surya’sSumati Surya’s research is focused on thecausal set approach to quantum gravity andrelated question of quantum interpretation inthe context of quantum cosmology. Last yearshe worked extensively on quantum vectormeasure theory. The need for a measurement-independent interpretation of quantumtheory has been most keenly felt in the studyof quantum cosmology. The dilemma of howto interpret quantum probabilities in theabsence of external measurements is mostacute when describing the physics of the earlyuniverse. In her work, done in collaborationwith scientists from Imperial College, London, itwas shown that the quantum measure can bereinterpreted as an additive measure, whichtakes its values in a Hilbert space constructedfrom the space of histories. This line ofinvestigation has a deep physical motivation,namely that of constructing observables inquantum gravity, without recourse tomeasuring devices. Within the standardinterpretation, no physical meaning can beascribed to quantum transitions in the earlyuniverse, and hence there is a strong need for
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ameasurementindependentformulation. Within thequantummeasureformulation,an exampleof anobservablewhich we canrelate toobservationallyis theexpansion ofthe universe
from an initial hot dense state. By assigning aquantum measure to this process, one canmake predictions from quantum gravity whichcould ultimately be tested by observations ofthe early universe.
Surya also addressed questions regarding thelow energy dynamics of causal sets. Using ananalytical continuation formulation in whichthe configuration space remains Lorentzian(the space of causal sets), a numerical MonteCarlo type study of causal set dynamics wasinitiated. Preliminary results confirmed thepredicted dominance of entropicconfigurations in the infinite temperature limit.The finite temperature case is currently underinvestigation.
It is of long standing interest in Lorentziangeometry to construct spacetime geometryand topology purely from its causal structure.While results for strongly causal spacetimeshave been known for some time, there wereuntil now only limited results for spacetimeswhich were future and past distinguishing, butnot necessarily strongly causal. Someinteresting features of these spacetimes havebeen examined by Surya and, in the process, anew topology was constructed purely from thecausal structure.
PPPPPoonam Mehtaoonam Mehtaoonam Mehtaoonam Mehtaoonam Mehta is currently a post doctoralfellow investigating the unique properties ofneutrinos - one of most elusive and hard todetect elemental particles. Another active areaof her research involves geometric phases. Amajor property of the neutrinos is theirsustained quantum coherence overastrophysical length scales. During the lastyear, she carried out a study of generalgeometric phases in the formalism of twoflavor neutrino oscillations. By using analogywith optics and employing the Pancharatnam’sprescription of quantum collapses, her studyled to the prediction that for the case of twoflavors and CP conservation, the geometricphase can take only topological values and is arobust quantity. However the topologicalrobustness can be destroyed once CP isviolated.
RRRRRoman Sveroman Sveroman Sveroman Sveroman Sverdlovdlovdlovdlovdlov is another of the postdoctoral fellows in the TP Group. The majortopics of his research throughout the year thatturned into manuscripts are: (i) Causal set as adiscretized phase spacetime; (ii) Completelylocal interpretation of quantum field theory;(iii) Incorporating particle creation andannihilation into Bohm’s Pilot Wave model andmore.
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facilities
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established facilities for laser cooling andtrapping of atoms. These include vacuumsystems, commercial and custom made lasers,spectroscopy equipment, standard electronicsand real time operating systems. A laboratoryis also set up for studying light propagation inrandom media. Another lab hosts anexperimental system to investigate quantumwalks of light. The system consists of threeMichelson optical interferometers, variousoptical components and acoustic-opticalmodulator. Two more labs allow forexperimental research of nonlinear opticalproperties of nanocomposites and dynamics,and spectral behavior of laser inducedplasmas. Standard and custom made facilitiesin the lab include a femtosecond laser systemwith amplifier, nanosecond Nd:YAG laser,spectrometers, monochromators, laser beamprofiler, ultra high vaccum chamber, X-ray andGamma-Ray detectors, experimental set up forz-scan and pump probe measurements, andmore.
3. SCM GROUP LABS
Chemistry LChemistry LChemistry LChemistry LChemistry Lababababab
The lab has all state of the art facilitiesnecessary for the synthesis and structurecharacterization of novel liquid crystalmaterials. Major equipment in the lab includespolarizing optical microscopes, highperformance liquid chromatograph,differential scanning calorimeter, elementalanalyzer, infrared and UV-Visiblespectrophotometer. Over 700 mesomorphicmolecules have been synthesized and
LABORATORIES
1. RADIO ASTRONOMY LAB (RAL)
The Radio Astronomy Lab (RAL) at RRI consistsof three divisions – Digital Signal Processing(DSP) Lab, Millimeter Wave and RF Lab, and X-Ray Astronomy Lab.
DSP LDSP LDSP LDSP LDSP Lababababab
The DSP lab is involved in the design,development and testing of digital receiversfor astronomy. The DSP lab team comprises ofhighly skilled engineers with expertise in thefield of digital circuit design and digital signalprocessing. RRI has a long history of designand development of a variety of digitalsystems (receivers, spectrometers, correlators)that have improved the capabilities of nationaland international telescope facilities. The labhas modern CAD design packages for thedevelopment of FPGA-based digital systems.
Millimeter Wave and RF LMillimeter Wave and RF LMillimeter Wave and RF LMillimeter Wave and RF LMillimeter Wave and RF Lababababab
The engineers from the RF lab are experiencedprofessionals with diverse skill-sets in thedesign and development of millimeter waveand RF systems. The lab is equipped with allnecessary fabrication and testing facilities forRF systems characterization. The group hasdesigned and built feeds, broadband antennasas well as standard and special purpose frontend receiver systems operating at wavelengthsfrom decameter to millimeter.
XXXXX-----RRRRRay Astray Astray Astray Astray Astronomy Lonomy Lonomy Lonomy Lonomy Lababababab
The X-ray lab is a fully equipped laboratory fordevelopment and testing of X-ray astronomicalinstrumentation. The infrastructure includes aclean room, X-ray generator, beam line,polarizer and monochromator, vacuumsystems, mounts and electronics forperformance evaluation of X-ray detectors.
2. LAMP GROUP LABS
Each faculty member of the LAMP group at RRIruns lab facilities specific to his/her individualresearch. Three of the members have well
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characterized in the Organic Chemistry Lab atRRI.
Physical MeasurPhysical MeasurPhysical MeasurPhysical MeasurPhysical Measurements Lements Lements Lements Lements Lababababab
The Physical Measurements Lab is equippedwith standard facilities for phase transitionstudies in liquid crystals, liquid crystalnanocomposites and various micellar solutions.The lab members are actively involved in thedevelopment of new precise techniques for avariety of phase transition measurements.Available equipment includes a polarizingoptical microscope, dielectric impedanceanalyzer and confocal microscope. Currently,there are experimental set ups for conoscopic,switching current and various electro-opticalmeasurements.
Liquid Crystal Display LLiquid Crystal Display LLiquid Crystal Display LLiquid Crystal Display LLiquid Crystal Display Lababababab
The LCD lab has basic facilities for fabricationof liquid crystal cells and small size(100mmX100mm) displays as well as standardelectronics equipment for their testing. Spincoating system, vacuum deposition unit,rubbing machine and temperature controlledovens are frequently used by the labmembers.
Rheology and Light Scattering LRheology and Light Scattering LRheology and Light Scattering LRheology and Light Scattering LRheology and Light Scattering Lababababab
The lab utilizes rheology and light scatteringtechniques to study the dynamics of softglassy materials and amphiphilic systems. Themost frequently used instrumentation in thelab includes a dynamic light scatterometer anda rheometer. Rheology, dynamic lightscatterometry and diffusing wavespectroscopy are some of the measurementtechniques used in the lab.
XXXXX-----RRRRRay Diffraction Lay Diffraction Lay Diffraction Lay Diffraction Lay Diffraction Lababababab
The X-ray lab is set up for investigating thephase behavior of various surfactants using X-ray diffraction. Polarizing light microscopy andsmall angle X-ray scattering techniques areoften used in the lab. To perform precise X-raymeasurements, the lab is equipped with a
confocal microscope, X-ray difractometer anda small angle X-ray scatterometer.
Biophysics LBiophysics LBiophysics LBiophysics LBiophysics Lababababab
The Biophysics lab is a self-sufficient lab wherevarious cells can be grown, manipulated andanalyzed. It is equipped with two fullymotorized microscopes allowing forfluorescence and face contrast microscopymeasurements, confocal microscope, biosafetycabinet for growing cells, incubators,centrifuge and a 3D microscope fordissections.
ElectrElectrElectrElectrElectrochemistry and Surface Science Lochemistry and Surface Science Lochemistry and Surface Science Lochemistry and Surface Science Lochemistry and Surface Science Lababababab
The lab performs controlled experiments ontest surfaces in electrochemical cells usingelectrochemical instruments such as apotestiostat, frequency response analyzer andlock-in amplifier. An electrochemical quartzcrystal microbalance is used to measure masschanges. Thin film characterization is donewith a variety ofscanning probetechniques like scanningtunneling microscopy,atomic forcemicroscopy and others.
4. MECHANICALENGINEERING
The mechanicalworkshop at RRI meetsthe mechanical designand fabrication needs ofRRI experimentalactivities. It has thenecessary machineryand a team of skilledpersonnel who canundertake fabrication of various sophisticatedmechanical hardware components forelectronics instrumentation as well as sheetmetal work for component, receiver enclosures,and system racks. The expertise of themechanical workshop team has been used inlarge projects like the fabrication and installation
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of 1100 helical antennas for the Mauritius Radiotelescope, design and fabrication of a lowfrequency antenna feed system for GMRT, andfabrication of a multi-band feed for the GreenBank telescope, West Virginia. Specific taskssuch as fabrication of precision mounts,positioners and cooling stages for the LAMP andSCM groups have been undertaken by themechanical workshop team as well.
LIBRARY
The library at RRI was founded by Sir C VRaman and ever since has served as a constantsource of both highly specialized and generalknowledge for the institute members.Throughout the years, the library hascontinuously expanded trying to provideadequate literature for the growing researchactivities at RRI. Currently, its total collection ofbooks and bound journals is close to 65000.The library has an extensive collection ofmaterials in the areas of research conducted atRRI – astronomy and astrophysics, classical andquantum optics, soft condensed matter,theoretical physics, electronics, digital signalprocessing, computer science, etc. The diverseinterests of the institute members are met bycollections of books on fine arts, travelling,general science, biography and photography.The non-book materials of the library includescientific slides, CD-ROMs, DVDs and audio andvideo tapes. The role of digital informationtoday demands flexible and adaptive librarianfunctionality. The RRI library is a partner inboth FORSA and CSIR-DST consortia and theexpansion of full text access to online journalsis one of its major priorities. It also maintains adigital repository of all publications publishedby RRI members as well as students’ thesesand dissertations. Open Public Access Catalog(OPAC) is available for access to readers withinand outside RRI. The library participates ininter library networking activities with variousother institutions like the Indian Institute ofScience, Indian Institute of Astrophysics,Jawaharlal Nehru Centre for Advanced
Scientific Research, National AerospaceLaboratories, National Centre for BiologicalSciences, TIFR Centre for ApplicableMathematics and others.
Last year, the library repository continued togrow. The newly included materials comprisedof English and Hindi books, non-bookmaterials, print journals and more than eightyonline journals. Various subscriptions throughFORSA and the National Knowledge ResourceConsortium of CSIR-DST facilitated enhancedaccess to over 4000 online journals. Papers andPhD theses published during the year wereadded to the digital repository and a CD mirrorserver was added to the library to facilitateaccess to its digital products.
COMPUTER FACILITIES
The various computing needs of the differentresearch and development groups at RamanResearch Institute are handled by ourcomputer division team. The computingfacilities consist of multi-CPU multi-coresystems accessed by users from their desktopsthrough a high speed internal LAN .Application-specific software packages alongwith development tools are available on theseplatforms. The campus network consists of aswitched Gigabit backbone on fiber and wired10/100 Mbps Ethernet to the desktops.Further mobility is assured by the securedwireless connection available on the campuspremises. A dedicated 10 Mbps line ensuresthe constant connectivity to the globalInternet community. A computer center is alsoavailable in the library for the needs ofstudents, staff and visitors.
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The computer facilities on campus continuedto be upgraded and improved during the lastyear. The eight node cluster was replaced witha high performance computer cluster withsixteen nodes. System and applicationpackages were upgraded, and the networksecurity improved. Backup and storagerequirements were addressed to meetincreased storage needs.
CAMPUS
The Raman Research Institute campus islocated in the northern part of Bangalore city.The campus covers an area of around 22 acres,where the bustling noise of the fast growingmetropolis gives way to the soothing soundsof nature, creating the necessary peacefulenvironment for creative work and research.The campus hosts all the office buildings,laboratories, a canteen, guest house and the10.4m telescope but when walking around oneis left with the impression that they are all tinyadditions to the prevailing natural garden.Most of the campus was landscaped by Sir C VRaman and the RRI Trust is proud to enforcepolicies that protect its unique naturalenvironment.
The guest house on campus has facilities tocomfortably accommodate distinguished
visitors and visiting academics, includingvisiting doctoral students. A canteen is alsopresent on campus to provide meals to allguests as well as lunch and refreshments to allRRI employees. Various gatherings, visitor talks,informal meetings, concerts and dinners takeplace at the Village – an ethnically designedarea providing a warm rustic touch to theoverall atmosphere on campus.
The building adjacent to the canteen houses asmall clinic where consultant medicalpractitioners pay visits at fixed hours on mostdays of the week.
Sport activities are envisioned to be animportant part of campus life. Therefore, thereare two badminton courts available for use bythe research faculty, staff and students.
Extensive renovations of major facilities andbuildings on campus took place during the lastyear. The Auditorium in the Main building wasequipped with better lighting and soundtechnology and the construction of a creativespace on the Library building rooftop wasfinished. Currently, the canteen building isunder major renovations that wouldmodernize and upgrade it to provide qualityservice to the institute members anddistinguished visitors in a faster and moreefficient manner.
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PhD PROGRAM
RRI offers a PhD program that gives enthusiasticand highly motivated students the opportunityto join the global research community. Theunique atmosphere of intellectual freedom allowsthe students at RRI to pursue their individualinterests within the broad areas of researchconducted at the Institute. As a result, studentsare challenged to engage their full creativepotential and develop the ability for conductingindependent research. Constant formal andinformal interactions with the faculty and otherstudents take the learning process outside of theclassroom and individuals’ office space,encouraging students to think and questioncritically others’ and their own understanding andknowledge. Such interactions also promote anopen minded attitude towards science andresearch. Attendance on national andinternational conferences exposes RRI students toa much larger and diverse research communitywhere they get a perspective of what the “bigpicture” in their field of research is.
Students at RRI are registered for a PhD degreewith the Jawaharlal Nehru University, New Delhi.RRI is also a participant in the Joint AstronomyProgram (JAP) with the Indian Institute ofScience, Bangalore and the Physics in BiologyProgram with the National Center for BiologicalSciences, Bangalore. Further detail about the PhDprogram, admission requirements and processcan be found on our website.
Currently, there are fifty seven students from allover India enrolled in the PhD program andconducting research with faculty members fromthe four groups in the institute – Astronomy andAstrophysics, Light and Matter Physics, SoftCondensed Matter Physics and TheoreticalPhysics.
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71
Last year five PhD degrees were awarded andfive were submitted for review.
POST DOCTORAL FELLOWSHIPPROGRAM
RRI offers a post doctoral fellowship programwhich is open for applications throughout theyear. The initial duration of the post doctoralfellowships is two years and is often extendedto three years.
Post-doctoral fellows work independently andhave the academic freedom of choice inresearch area and collaboration. Even thoughpost doctoral fellows are not required to workin any specific research program or beattached to specific research staff of theInstitute, it is desirable that they haveprofessional research interest and proven trackrecord in areas with significant overlap orassociation with the ongoing and envisagedactivities at the Institute. Participation of thefellows in the academic activities of theInstitute, student supervision as co-guides andcollaboration with other research staff is highlyencouraged.
Candidates who have already held at least oneposition as a post doctoral researcher can alsoapply for a limited number of PancharatnamFellowships offered at RRI. Applications areaccepted throughout the year and theprocessing time takes between four to sixmonths. The selected candidates are awardedthe Pancharatnam Fellowship for a period ofthree years.
Further details about the post doctoral andPancharatnam fellowships at RRI can be foundon our website www.rri.res.in.
Currently, there are twelve post doctoralfellows at RRI coming from across the countryand abroad. Their research background,diverse scientific interests and future goals playimportant role in the overall academic andresearch dynamics of the institute.
VISITING STUDENTS PROGRAM
Raman Research Institute places highimportance on its Visiting Student Program(VSP) which was introduced in 2007. VSP at RRIoffers research experience to students, whoare currently pursuing their undergraduate ormaster’s studies. The program runs year-roundand its duration ranges from 6 weeks up toone year depending on individual cases. At thebeginning a suitable project is identified foreach student. While working on their projects,VSP students are closely advised by a researchfaculty or scientific staff member of theInstitute. They are encouraged to interact withother staff members and graduate studentslearning the importance of sharing knowledgeand exchange of ideas among researchers. Theprogram is designed such that students getexposed to some of the real challenges in theworld of scientific research and acquireimportant skills that would help them in theirfuture research pursuits.
The Summer Student Program at RRI is similarto the Visiting Student Program but it runsonly between May 1st and June 30th of eachyear. It provides the opportunity to up totwenty selected candidates to becomeinvolved in short term research projects underthe guidance of a research faculty member.
Since the program initiation, the number ofVSP students has progressively increasedthrough the years. During the last year alone, atotal of 101 students from different parts ofthe country were partof the VisitingStudent Program atRRI.
All those interested tojoin the VisitingStudent Program atRRI should visit ourwebsite to learn moreabout the eligibilitycriteria andapplication process.
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people at RRI
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73
V RV RV RV RV Radhakrishnan adhakrishnan adhakrishnan adhakrishnan adhakrishnan (DistinguishedProfessor Emeritus)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: neutronstars, pulsars, locomotion
Email: Email: Email: Email: Email: [email protected]
RRRRRavi Subrahmanyan avi Subrahmanyan avi Subrahmanyan avi Subrahmanyan avi Subrahmanyan ( RRIDirector)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests:ests:ests:ests:ests:observational cosmology,extragalactic astronomy,antennas and signal processing
Email: Email: Email: Email: Email: [email protected]
N Udaya Shankar N Udaya Shankar N Udaya Shankar N Udaya Shankar N Udaya Shankar (Coordinator)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: sky surveys,detection of EoR,instrumentation and signalprocessing for radio astronomy
Email: Email: Email: Email: Email: [email protected]
Anish RAnish RAnish RAnish RAnish Roshioshioshioshioshi
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: The Galaxyand Interstellar medium,Instrumentation and Signalprocessing
Email: Email: Email: Email: Email: [email protected]
R BhandariR BhandariR BhandariR BhandariR Bhandari
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: topologicalphases, polarization optics
Email: Email: Email: Email: Email: [email protected]
Biman NathBiman NathBiman NathBiman NathBiman Nath
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: cosmologyand structure formation,extragalactic astronomy
Email: Email: Email: Email: Email: [email protected]
A A DeshpandeA A DeshpandeA A DeshpandeA A DeshpandeA A Deshpande
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: neutronstars, pulsars & transients,instrumentation and signalprocessing
Email: Email: Email: Email: Email: [email protected]
B RB RB RB RB Rameshameshameshameshamesh
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: diffusematter in our and othergalaxies, analog & digital signalprocessing, (sub)millimeterwavetelescopes
Email: Email: Email: Email: Email: [email protected]
S SridharS SridharS SridharS SridharS Sridhar
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: dynamoaction due to turbulence inshear flows, MHD turbulence,stellar dynamics in galactic nuclei
Email: Email: Email: Email: Email: [email protected]
C R SubramanyaC R SubramanyaC R SubramanyaC R SubramanyaC R Subramanya
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: cosmology,extragalactic radio sources,surveys, instrumentation andsignal processing
Email: Email: Email: Email: Email: [email protected]
Biswajit PBiswajit PBiswajit PBiswajit PBiswajit Paulaulaulaulaul
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: X-raybinaries, transients, X-rayinstrumentation and signalprocessing
Email: Email: Email: Email: Email: [email protected]
Shiv Kumar SethiShiv Kumar SethiShiv Kumar SethiShiv Kumar SethiShiv Kumar Sethi
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: cosmologyand structure formation,reionization era, cosmologicalmagnetic fields
Email: Email: Email: Email: Email: [email protected]
Dwarakanath K SDwarakanath K SDwarakanath K SDwarakanath K SDwarakanath K S
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests:ests:ests:ests:ests:extragalactic astronomy, clustersof galaxies, halo and relic radiosources
Email: Email: Email: Email: Email: [email protected]
LLLLLakshmi Saripalli akshmi Saripalli akshmi Saripalli akshmi Saripalli akshmi Saripalli (RRI Trustfunded position)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests:ests:ests:ests:ests: morphologyand life-cycle of radio galaxies,surveys
Email:Email:Email:Email:Email: [email protected]
Harish VedanthamHarish VedanthamHarish VedanthamHarish VedanthamHarish Vedantham (ResearchAssociate)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: epoch of re-ionization, radio telescopeinstrumentation, synthesisimaging
Email: Email: Email: Email: Email: [email protected]
Shashikant Shashikant Shashikant Shashikant Shashikant (Post DoctoralFellow)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests:ests:ests:ests:ests: physicalcosmology, cosmic backgroundradiation, large-scale structure ofthe universe
Email: Email: Email: Email: Email: [email protected]
Siddharth Malu Siddharth Malu Siddharth Malu Siddharth Malu Siddharth Malu (Post DoctoralFellow)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests:ests:ests:ests:ests: galaxyclusters, cosmic microwavebackground
Email: Email: Email: Email: Email: [email protected]
ASTRONOMY AND ASTROPHYSICS
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research faculty
74
LIGHT AND MATTERPHYSICS
RRRRReji Philip eji Philip eji Philip eji Philip eji Philip (Coordinator)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests:ests:ests:ests:ests: nonlinearoptics, intense laser fieldinteractions, laser inducedplasmas
Email:Email:Email:Email:Email: [email protected]
Hema RHema RHema RHema RHema Ramachandranamachandranamachandranamachandranamachandran
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: quantumcomputing, light propagation inrandom media, novel opticalapplications of nanomaterials
Email: Email: Email: Email: Email: [email protected]
Sadiq RSadiq RSadiq RSadiq RSadiq Rangwalaangwalaangwalaangwalaangwala
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: ultra coldmolecules, ion trapping, atomsand molecules in external fields
Email: Email: Email: Email: Email: [email protected]
Andal NarayananAndal NarayananAndal NarayananAndal NarayananAndal Narayanan
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: quantumoptics, magneto-optical traps,electromagnetically inducedtransparency
Email: Email: Email: Email: Email: [email protected]
Sunita Sharma Sunita Sharma Sunita Sharma Sunita Sharma Sunita Sharma (Post DoctoralFellow)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests:ests:ests:ests:ests: ultrafast andnonlinear optics
Email:Email:Email:Email:Email: [email protected]
Solomon Ivan Solomon Ivan Solomon Ivan Solomon Ivan Solomon Ivan (Post DoctoralFellow)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests:ests:ests:ests:ests: quantuminformation theory, theory ofentanglement
Email:Email:Email:Email:Email: [email protected]
SOFT CONDENSEDMATTER
Sandeep Kumar Sandeep Kumar Sandeep Kumar Sandeep Kumar Sandeep Kumar (Coordinator)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: chemicalsynthesis of liquid crystals andtheir applications
Email: Email: Email: Email: Email: [email protected]
RRRRRaghunathan V A aghunathan V A aghunathan V A aghunathan V A aghunathan V A
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: Amphiphilicsystems, membranes, self-assembly and phase behavior ofsurfactant polyelectrolytecomplexes
Email: Email: Email: Email: Email: [email protected]
Arun RArun RArun RArun RArun Royoyoyoyoy
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: Phasetransitions and electro-opticproperties of liquid crystals,physics of nanomaterials andnanocomposites.
Email: Email: Email: Email: Email: [email protected]
Pratibha RPratibha RPratibha RPratibha RPratibha R
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: liquidcrystals, nanocomposites
Email: Email: Email: Email: Email: [email protected]
LLLLLakshminarayanan Vakshminarayanan Vakshminarayanan Vakshminarayanan Vakshminarayanan V
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests:ests:ests:ests:ests:Electrochemistry of surfaces andinterfaces, electron transferprocesses
Email: Email: Email: Email: Email: [email protected]
RRRRRanjini Bandyopadhyayanjini Bandyopadhyayanjini Bandyopadhyayanjini Bandyopadhyayanjini Bandyopadhyay
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: Copolymer-surfactant interactions, drugdelivery systems, non-Newtonianflows, gels, soft glasses,granular media
Email: Email: Email: Email: Email: [email protected]
Ruckmongathan T NRuckmongathan T NRuckmongathan T NRuckmongathan T NRuckmongathan T N
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: liquid crystaldisplays, addressing, controllers
Email: Email: Email: Email: Email: [email protected]
YYYYYashodhan Hatwalneashodhan Hatwalneashodhan Hatwalneashodhan Hatwalneashodhan Hatwalne
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests:ests:ests:ests:ests:Phenomenological theory ofliquid crystals, membranes andpolymer crystallization
Email: Email: Email: Email: Email: [email protected]
Pramod PullarkatPramod PullarkatPramod PullarkatPramod PullarkatPramod Pullarkat
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: Biophysics incell dynamics, cell cytoskeleton,transport and dynamics inaxons
Email: Email: Email: Email: Email: [email protected]
B K Sadashiva B K Sadashiva B K Sadashiva B K Sadashiva B K Sadashiva (INSA SeniorScientist)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: chemistry ofliquid crystalline materials,intelligent design and synthesisof mesogens
Email:Email:Email:Email:Email: [email protected]
N V Madhusudhana N V Madhusudhana N V Madhusudhana N V Madhusudhana N V Madhusudhana (INSA SeniorScientist)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: softcondensed matter, liquid crystals
Email: Email: Email: Email: Email: [email protected]
Soma Datta Soma Datta Soma Datta Soma Datta Soma Datta (Post DoctoralFellow)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests:ests:ests:ests:ests: Phasetransitions and electro optics ofliquid crystals.
Email:Email:Email:Email:Email: [email protected]
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Meenal Gupta Meenal Gupta Meenal Gupta Meenal Gupta Meenal Gupta (Post DoctoralFellow)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests:ests:ests:ests:ests: physicalproperties of liquid crystals usingdifferent experimentaltechniques
Email:Email:Email:Email:Email: [email protected]
Kavitha GKavitha GKavitha GKavitha GKavitha G
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests:ests:ests:ests:ests: structureand phase behavior of liquidcrystals
Email:Email:Email:Email:Email: [email protected]
THEORETICAL PHYSICS
Abhishek Dhar Abhishek Dhar Abhishek Dhar Abhishek Dhar Abhishek Dhar (Coordinator)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: non-equilibrium statistical mechanics,soft condensed matter physics
Email: Email: Email: Email: Email: [email protected]
Sanjib SabhapanditSanjib SabhapanditSanjib SabhapanditSanjib SabhapanditSanjib Sabhapandit
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: statisticalphysics, extreme value statistics
Email: Email: Email: Email: Email: [email protected]
Joseph SamuelJoseph SamuelJoseph SamuelJoseph SamuelJoseph Samuel
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: generalrelativity, optics, soft condensedmatter physics
Email: Email: Email: Email: Email: [email protected]
Madan RMadan RMadan RMadan RMadan Raoaoaoaoao
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: softcondensed matter physics,physics in biology
Email: Email: Email: Email: Email: [email protected]
B R IyerB R IyerB R IyerB R IyerB R Iyer
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: generalrelativity, gravitational waves
Email: Email: Email: Email: Email: [email protected]
Sumati SuryaSumati SuryaSumati SuryaSumati SuryaSumati Surya
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: classical andquantum gravity
Email: Email: Email: Email: Email: [email protected]
Madhavan VaradarajanMadhavan VaradarajanMadhavan VaradarajanMadhavan VaradarajanMadhavan Varadarajan
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests: ests: ests: ests: ests: classical andquantum Gravity
Email: Email: Email: Email: Email: [email protected]
N Kumar N Kumar N Kumar N Kumar N Kumar (Homi BhabhaDistinguished Professor)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests:ests:ests:ests:ests: randomness,dissipation, and decoherence incondensed matter
Email:Email:Email:Email:Email: [email protected]
Supurna Sinha Supurna Sinha Supurna Sinha Supurna Sinha Supurna Sinha (ResearchAssociate)
RRRRResearesearesearesearesearch interch interch interch interch interests: ests: ests: ests: ests: non-equilibrium statistical mechanics,soft condensed matter physics
Email: Email: Email: Email: Email: [email protected]
Alok LAlok LAlok LAlok LAlok Laddha addha addha addha addha (Post DoctoralFellow)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests:ests:ests:ests:ests: loopquantum gravity
Email:Email:Email:Email:Email: [email protected]
PPPPPoonam Mehtaoonam Mehtaoonam Mehtaoonam Mehtaoonam Mehta(Post DoctoralFellow)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests:ests:ests:ests:ests: neutrinophysics and geometric phase
Email:Email:Email:Email:Email: [email protected]
RRRRRoman Sveroman Sveroman Sveroman Sveroman Sverdlovdlovdlovdlovdlov(Post DoctoralFellow)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests:ests:ests:ests:ests: quantumgravity, causal set theory
Email:Email:Email:Email:Email: [email protected]
Ryuichi FRyuichi FRyuichi FRyuichi FRyuichi Fujitaujitaujitaujitaujita(Post DoctoralFellow)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests:ests:ests:ests:ests: gravitationalwaves, general relativity
Email:Email:Email:Email:Email: [email protected]
Samarth Chandra Samarth Chandra Samarth Chandra Samarth Chandra Samarth Chandra (Post DoctoralFellow)
RRRRResearesearesearesearesearch Interch Interch Interch Interch Interests:ests:ests:ests:ests: statisticalmechanics, biophysics
Email:Email:Email:Email:Email: [email protected]
Abhishek Chaudhuri Abhishek Chaudhuri Abhishek Chaudhuri Abhishek Chaudhuri Abhishek Chaudhuri (PostDoctoral Fellow)
Note:Note:Note:Note:Note: Fellowship ended on Sept4 2009
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RADIO ASTRONOMYLAB
M R Gopala [email protected]
K B Raghavendra [email protected]
P S Sasi [email protected]
LIGHT AND MATTERPHYSICS
SOFT CONSENSEDMATTER
Mohammed [email protected]
N Ravi [email protected]
MECHANICALENGINEERINGSERVICES
C M Ateequlla, [email protected]
M Achankunju
I Charles Paul
V Dhamodharan
R Durai Chelvan
R Elumalai
K O Francis
V Gokula Chandran
N Gopal
V K Muthu (upto 30.6.2009)
M Mani
K M Mohandas
S Sunderaj (upto 30.6.2009)
V Nagarajan
N Narayanaswamy
T Puttaswamy
D Sunand
M Suresh Kumar
V Venu
COMPUTERS
R Nanda Kumar, [email protected]
Jacob [email protected]
Krishna Murthy [email protected]
GAURIBIDANURTELESCOPE
H A Aswathappa
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scientific/technical staff
77
ASTRONOMY ANDASTROPHYSICS
PPPPPeeyush Prasadeeyush Prasadeeyush Prasadeeyush Prasadeeyush Prasad
RESEARCH INTERESTS: radioastronomy instrumentation
ADVISOR: C R Subramanya
RRRRRaju Raju Raju Raju Raju Ramakrishna Baddiamakrishna Baddiamakrishna Baddiamakrishna Baddiamakrishna Baddi
Research Interests: Physics ofinterstellar medium,observational and theoreticalastrophysics
EMAIL: [email protected]
ADVISOR: Anish Roshi
Ruta KaleRuta KaleRuta KaleRuta KaleRuta Kale
RESEARCH INTERESTS: Galaxyclusters, Magnetic fields in intra-cluster medium
EMAIL: [email protected]
ADVISOR: K S Dwarakanth
Wasim RWasim RWasim RWasim RWasim Rajaajaajaajaaja
RESEARCH INTERESTS: neutronstars, pulsars & transients,instrumentation and signalprocessing
EMAIL: [email protected]
ADVISOR: A A Deshpande
YYYYYogesh Maan ogesh Maan ogesh Maan ogesh Maan ogesh Maan (JAP student)
RESEARCH INTERESTS: neutronstars, pulsars & transients,instrumentation and signalprocessing
EMAIL: [email protected]
ADVISOR: A A Deshpande
Mamta Gulati Mamta Gulati Mamta Gulati Mamta Gulati Mamta Gulati (JAP student)
RESEARCH INTERESTS: Waves anddynamics in disks
EMAIL: [email protected]
ADVISOR: S Sridhar
Nishant Kumar Singh Nishant Kumar Singh Nishant Kumar Singh Nishant Kumar Singh Nishant Kumar Singh (JAPstudent)
RESEARCH INTERESTS:Astrophysical flows
EMAIL: [email protected]
ADVISOR: S Sridhar
Kanhaiya LKanhaiya LKanhaiya LKanhaiya LKanhaiya Lal Pal Pal Pal Pal Pandeyandeyandeyandeyandey
RESEARCH INTERESTS:cosmology and structureformation, reionization era
EMAIL: [email protected]
ADVISOR: Shiv Sethi
Nipanjana PNipanjana PNipanjana PNipanjana PNipanjana Patra atra atra atra atra (JAP student)
RESEARCH INTERESTS:Cosmology, global 21 cm, EOR
EMAIL: [email protected]
ADVISOR: Ravi Subramanyan
ChandrChandrChandrChandrChandreyee Maitra eyee Maitra eyee Maitra eyee Maitra eyee Maitra (JAPstudent)
RESEARCH INTERESTS: X rayPolarisation , polarimeter,spectral studies of X ray binaries
EMAIL: [email protected]
ADVISOR: Dr. Biswajit Paul
Kshitij Thorat Kshitij Thorat Kshitij Thorat Kshitij Thorat Kshitij Thorat (JAP student)
RESEARCH INTERESTS: RadioAstronomy, optical astronomy,active galactic nucleus (AGN)evolution
EMAIL: [email protected]
ADVISOR: Ravi Subramanyan/Lakshmi Saripalli
Mahavir SharmaMahavir SharmaMahavir SharmaMahavir SharmaMahavir Sharma
RESEARCH INTERESTS:cosmology and structureformation, extragalacticastronomy
EMAIL: [email protected]
ADVISOR: Biman Nath
LIGHT AND MATTERPHYSICS
Seunghyun LSeunghyun LSeunghyun LSeunghyun LSeunghyun Leeeeeeeeee
RESEARCH INTERESTS: Atom-Ioninteraction
EMAIL: [email protected]
ADVISOR: Sadiq Ragwala
ArArArArArchana Sharmachana Sharmachana Sharmachana Sharmachana Sharma
RESEARCH INTERESTS: quantuminteractions with cold atoms,molecules and ions
EMAIL: [email protected]
ADVISOR: Sadiq Ragwala
Arijit SharmaArijit SharmaArijit SharmaArijit SharmaArijit Sharma
RESEARCH INTERESTS: lasercooling of atoms, coldmolecules, optical lattices andBEC
EMAIL: [email protected]
ADVISOR: Sadiq Rangwala
Deepak PDeepak PDeepak PDeepak PDeepak Pandeyandeyandeyandeyandey
RESEARCH INTERESTS: lasercooling of atoms, quantumcomputation
EMAIL: [email protected]
ADVISOR: Hema Ramachandran
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PhD students
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Nandan SatapathyNandan SatapathyNandan SatapathyNandan SatapathyNandan Satapathy
RESEARCH INTERESTS: coldatoms, BEC, optical lattices
EMAIL: [email protected]
ADVISOR: Hema Ramachandran
RRRRRavi Kavi Kavi Kavi Kavi K
RESEARCH INTERESTS: lasercooling of atoms, trapping ofions, atom-ion interaction,molecule
formation mechanisms
EMAIL: [email protected]
ADVISOR: Sadiq Rangwala
Suchand SandeepSuchand SandeepSuchand SandeepSuchand SandeepSuchand Sandeep
RESEARCH INTERESTS: plasmaphysics, intense laser matterinteractions, nonlinear optics
EMAIL: [email protected]
ADVISOR: Reji Philip
Jagdish Chandra JoshiJagdish Chandra JoshiJagdish Chandra JoshiJagdish Chandra JoshiJagdish Chandra Joshi
RESEARCH INTERESTS: quantumchemistry
EMAIL: [email protected]
ADVISOR: Sadiq Rangwala
Jyothi SJyothi SJyothi SJyothi SJyothi S
RESEARCH INTERESTS: quantuminteractions of atoms, moleculesand ions
EMAIL: [email protected]
ADVISOR: Sadiq Ragwala
TTTTTridib Rridib Rridib Rridib Rridib Rayayayayay
RESEARCH INTERESTS: quantuminteractions of atoms, moleculesand ions
EMAIL: [email protected]
ADVISOR: Sadiq Ragwala
SOFT CONDENSEDMATTER
Alpana NayakAlpana NayakAlpana NayakAlpana NayakAlpana Nayak
NOTE: Graduated in April 2009
Bharat KumarBharat KumarBharat KumarBharat KumarBharat Kumar
RESEARCH INTERESTS:Electrochemistry of surfaces andinterfaces, electron transferprocesses
EMAIL: [email protected]
ADVISOR: V Lakshminarayan
Bibhu RBibhu RBibhu RBibhu RBibhu Ranjan Sarangianjan Sarangianjan Sarangianjan Sarangianjan Sarangi
RESEARCH INTERESTS:Experimental Biophysics,Membrane Physics
EMAIL: [email protected]
ADVISOR: V A Raghunathan
Brindaban KunduBrindaban KunduBrindaban KunduBrindaban KunduBrindaban Kundu
RESEARCH INTERESTS: liquidcrystals, nanocomposites
EMAIL: [email protected]
ADVISOR: R Pratibha
Hari Krishna BisoyiHari Krishna BisoyiHari Krishna BisoyiHari Krishna BisoyiHari Krishna Bisoyi
RESEARCH INTERESTS: chemistryof liquid crystals
EMAIL: [email protected]
ADVISOR: Sandeep Kumar
A JayakA JayakA JayakA JayakA Jayakumarumarumarumarumar
RESEARCH INTERESTS: theory ofliquid crystals
EMAIL: [email protected]
ADVISOR: Yashodhan Hatwalne
D H NagarajuD H NagarajuD H NagarajuD H NagarajuD H Nagaraju
RESEARCH INTERESTS:Electrochemistry of surfaces andinterfaces, electron transferprocesses
EMAIL: [email protected]
ADVISOR: V Lakshminarayan
RRRRRadhakrishnan A Vadhakrishnan A Vadhakrishnan A Vadhakrishnan A Vadhakrishnan A V
RESEARCH INTERESTS:amphiphilic systems, surfactants
EMAIL: [email protected]
ADVISOR: V A Raghunathan
Mohammed Arif KamalMohammed Arif KamalMohammed Arif KamalMohammed Arif KamalMohammed Arif Kamal
RESEARCH INTERESTS: Modelmembranes
EMAIL: [email protected]
ADVISOR: V A Raghunathan
S RS RS RS RS Radhikaadhikaadhikaadhikaadhika
RESEARCH INTERESTS: liquidcrystals, nanocomposites
EMAIL: [email protected]
ADVISOR: R Pratibha
S MadhukarS MadhukarS MadhukarS MadhukarS Madhukar
RESEARCH INTERESTS:surfactants, amphiphilic systems
EMAIL: [email protected]
ADVISOR: V A Raghunathan
RRRRRajib Basakajib Basakajib Basakajib Basakajib Basak
RESEARCH INTERESTS: Dynamicsand Rheology of Soft GlassyMaterials
EMAIL: [email protected]
ADVISOR: RanjiniBandyopadhyaya
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Debasish SahaDebasish SahaDebasish SahaDebasish SahaDebasish Saha
RESEARCH INTERESTS: Structureand Dynamics of Colloids,Rheology of Soft Glassy Materialand Flow Behavior of Soft Solids
EMAIL: [email protected]
ADVISOR: Dr. RanjiniBandyopadhyay
RRRRRenu Venu Venu Venu Venu Vishavkarmaishavkarmaishavkarmaishavkarmaishavkarma
RESEARCH INTERESTS: biophysics
EMAIL: [email protected]
ADVISOR: Pramod Pullarkat
Santosh GuptaSantosh GuptaSantosh GuptaSantosh GuptaSantosh Gupta
RESEARCH INTERESTS:surfactants, amphiphilic systems
EMAIL: [email protected]
ADVISOR: V A Raghunathan
Seshagiri RSeshagiri RSeshagiri RSeshagiri RSeshagiri Raoaoaoaoao
RESEARCH INTERESTS: biophysics
EMAIL: [email protected]
ADVISOR: Pramod Pullarkat
P R VenkatramananP R VenkatramananP R VenkatramananP R VenkatramananP R Venkatramanan
RESEARCH INTERESTS: LiquidCrystals, Membranes
EMAIL: [email protected]
ADVISOR: Yashodhan Hatwalne
RRRRRakesh Kumar Pakesh Kumar Pakesh Kumar Pakesh Kumar Pakesh Kumar Pandeyandeyandeyandeyandey
RESEARCH INTERESTS:Electrochemistry, Materialscience, Electrocatalysis
EMAIL: [email protected]
ADVISOR: Prof. V.Lakshminarayanan
Satyam Kumar GuptaSatyam Kumar GuptaSatyam Kumar GuptaSatyam Kumar GuptaSatyam Kumar Gupta
RESEARCH INTERESTS: liquidcrystal synthesis andcharacterization
EMAIL: [email protected]
ADVISOR: Sandeep Kumar
P SurP SurP SurP SurP Suresh Kumaresh Kumaresh Kumaresh Kumaresh Kumar
RESEARCH INTERESTS:Electrochemistry of surfaces andinterfaces, electron transferprocesses
EMAIL: [email protected]
ADVISOR: V Lakshminarayanan
TTTTTripta Bhatiaripta Bhatiaripta Bhatiaripta Bhatiaripta Bhatia
RESEARCH INTERESTS: theory ofliquid crystals
EMAIL: [email protected]
ADVISOR: Yashodhan Hatwalne
Anagha DatarAnagha DatarAnagha DatarAnagha DatarAnagha Datar
RESEARCH INTERESTS: biophysics
EMAIL: [email protected]
ADVISOR: Pramod Pullarkat
P K ShabeebP K ShabeebP K ShabeebP K ShabeebP K Shabeeb
RESEARCH INTERESTS: rheologyof soft matter systems
EMAIL: [email protected]
ADVISOR: Ranjini Bandyopadhyay
Avinash B SAvinash B SAvinash B SAvinash B SAvinash B S
RESEARCH INTERESTS:Electrochemistry of surfaces andinterfaces, electron transferprocesses
EMAIL: [email protected]
ADVISOR: V Lakshminarayan
Samim AliSamim AliSamim AliSamim AliSamim Ali
RESEARCH INTERESTS: rheologyof soft matter systems
EMAIL: [email protected]
ADVISOR: Ranjini Bandyopadhyay
Swamynathan KSwamynathan KSwamynathan KSwamynathan KSwamynathan K
RESEARCH INTERESTS: chemistryof liquid crystals
EMAIL: [email protected]
ADVISOR: Sandeep Kumar
THEORETICAL PHYSICS
Anirban PAnirban PAnirban PAnirban PAnirban Polleyolleyolleyolleyolley
RESEARCH INTERESTS: softcondensed matter
EMAIL: [email protected]
ADVISOR: Madan Rao
Anupam KunduAnupam KunduAnupam KunduAnupam KunduAnupam Kundu
RESEARCH INTERESTS: softcondensed matter and statisticalmechanics
EMAIL: [email protected]
ADVISOR: Abhishek Dhar
Chandrakant Mishra Chandrakant Mishra Chandrakant Mishra Chandrakant Mishra Chandrakant Mishra (JAPstudent)
RESEARCH INTERESTS:gravitational radiation andgeneral relativity
EMAIL: [email protected]
ADVISOR: Bala Iyer
Pragya SrivastavaPragya SrivastavaPragya SrivastavaPragya SrivastavaPragya Srivastava
RESEARCH INTERESTS: biologicalsystems - theoretical studies ofactive processes in living cells.
EMAIL: [email protected]
ADVISOR: Madan Rao
Suchana SethSuchana SethSuchana SethSuchana SethSuchana Seth
RESEARCH INTERESTS: Non-equilibrium statistical mechanics
EMAIL: [email protected]
ADVISOR: Abhishek Dhar
Anjan RAnjan RAnjan RAnjan RAnjan Royoyoyoyoy
RESEARCH INTERESTS: statisticalmechanics
EMAIL: [email protected]
ADVISOR: Abhishek Dhar
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Chaitra ShrChaitra ShrChaitra ShrChaitra ShrChaitra Shreepad Hegdeeepad Hegdeeepad Hegdeeepad Hegdeeepad Hegde
RESEARCH INTERESTS: theoreticalphysics, statistical mechanics
EMAIL: [email protected]
ADVISOR: Abhishek Dhar
Prasad V V Prasad V V Prasad V V Prasad V V Prasad V V
RESEARCH INTERESTS: theoreticalphysics, statistical mechanics
EMAIL: [email protected]
ADVISOR: Sanjib Sabhapandit
Suman Gaurab DasSuman Gaurab DasSuman Gaurab DasSuman Gaurab DasSuman Gaurab Das
RESEARCH INTERESTS: theoreticalphysics, statistical mechanics
EMAIL: [email protected]
ADVISOR: Abhishek Dhar
Arnab PArnab PArnab PArnab PArnab Palalalalal
RESEARCH INTERESTS: theoreticalphysics, statistical mechanics
EMAIL: [email protected]
ADVISOR: Sanjib Sabhapandit
Dibyendu RDibyendu RDibyendu RDibyendu RDibyendu Royoyoyoyoy
NOTE: Graduated in August 2009
Kripa GKripa GKripa GKripa GKripa G
NOTE: Graduated in May 2009
Siddhartha Sinha Siddhartha Sinha Siddhartha Sinha Siddhartha Sinha Siddhartha Sinha (JAP student)
NOTE: Graduated in July 2009
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visiting scientists
AAAAASTRONOMY AND ASTRONOMY AND ASTRONOMY AND ASTRONOMY AND ASTRONOMY AND ASTROPHYSICSSTROPHYSICSSTROPHYSICSSTROPHYSICSSTROPHYSICS
P Sreekumar
Tarun Deep Saini
Vinod Krishan
LIGHT AND MALIGHT AND MALIGHT AND MALIGHT AND MALIGHT AND MATTER PHYSICSTTER PHYSICSTTER PHYSICSTTER PHYSICSTTER PHYSICS
R Srikanth
R Srinivasan
RADIO ARADIO ARADIO ARADIO ARADIO ASTRONOMY LABSTRONOMY LABSTRONOMY LABSTRONOMY LABSTRONOMY LAB
A Krishnan
ADJUNCT PROFESSORSADJUNCT PROFESSORSADJUNCT PROFESSORSADJUNCT PROFESSORSADJUNCT PROFESSORS
Ramanath Cowsik
Anders Kastberg
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Dr. K Kasturirangan Member, Planning CommissionChairman
Prof. P K Kaw Director, Institute of Plasma ResearchGandhinagar 382 428
Prof. V Radhakrishnan Member-SecretaryRaman Research Institute TrustBangalore 560 080
Dr.T Ramasami Secretary, Department of Science & TechnologyMinistry of Science & TechnologyNew Delhi 110 016
Prof. Ravi Subrahmanyan Director, Raman Research InstituteBangalore 560 080
Prof. O Siddiqi National Centre for Biological SciencesTata Institute of Fundamental ResearchBangalore 560 065
Mr. K P Pandian Joint Secretary & Financial AdviserMinistry of Science & TechnologyGovernment of India, New Delhi 110 016
Prof. A K Sood Physical & Mathematical Sciences DivisionIndian Institute of ScienceBangalore 560012
FINANCE COMMITTEEFINANCE COMMITTEEFINANCE COMMITTEEFINANCE COMMITTEEFINANCE COMMITTEE
Dr. K Kasturirangan Member, Planning CommissionChairman
Mr. K P Pandian Joint Secretary & Financial AdviserMinistry of Science & TechnologyGovernment of India, New Delhi 110 016
Prof. V Radhakrishnan Member-SecretaryRaman Research Institute TrustBangalore 560 080
Prof. Ravi Subrahmanyan Director, Raman Research InstituteBangalore 560 080
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Council
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ADMINISTRATIONK Krishnama Raju(Admin. Officer)[email protected]
K Raghunatha(Dy. Admin. Officer)[email protected]
Marisa D’[email protected]
G V Indira
GROUP SECRETARIES
AstrAstrAstrAstrAstromony and Astromony and Astromony and Astromony and Astromony and Astrophysicsophysicsophysicsophysicsophysics
Vidyamani [email protected]
Soft Condensed MatterSoft Condensed MatterSoft Condensed MatterSoft Condensed MatterSoft Condensed Matter
Radhakrishna [email protected]
Light and Matter PhysicsLight and Matter PhysicsLight and Matter PhysicsLight and Matter PhysicsLight and Matter Physics
S Harini [email protected]
TheorTheorTheorTheorTheoretical Physicsetical Physicsetical Physicsetical Physicsetical Physics
RAL LRAL LRAL LRAL LRAL Lababababab
Mamatha Bai [email protected]
ACCOUNTSP V Subramanya(Accounts Officer)
V Raghunath
R Ramesh (Internal Auditor)
PURCHASES Srinivasa Murthy(upto 26.2.10)
C N Ramamurthy (In-charge)
M Prema
G Gayathri
STORESB Srinivasa Murthy (In-charge)
M V Subramanyam
LIBRARYY M Patil (Librarian)(upto 26.2.10)
S Geetha
Girija Srinivasan(upto 31.12.09)
Hanumappa
Kiran P Savanur
M Manjunath
M N Nagaraj
Vrinda J Benegal
Raju Varghese (Graphic Arts)
Support StaffSupport StaffSupport StaffSupport StaffSupport Staff
K Chowdasetty
C Elumalai
UPKEEPHanumantha
Jayamma
K N Kawalappa
D Krishna
C Lakshmamma
T Mahadeva
T Murali
Narayana
Sidde Gowda
V Venkatesh
ESTATES & BUILDINGSG B Suresh (Civil Engineer)
R Sasidharan (Supervisor)
R Anantha Subba Rao(Consultant)
S Anantha Raman
K Bhoopalan
Gunashekar
C Haridas
K Palani
M Rajagopal
K G Narasimhalu
T Subramaniyam Naidu(upto 30.6.09)
M Ramesh
A Ramanna
Ranjithamma
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other staff
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SECURITYV Jayaraman (In-charge)
B M Basavarajaiah
U A Earappa
H Gangaiah
Keshavamurthy
Suresha
K. Krishnappa
Munihobalaiah
K Pushparaj
O M Ramachandra
G Ramakrishna
M Sannaiah
H Vaderappa
ConsultantsConsultantsConsultantsConsultantsConsultants
K Balaji
S Nagaraja
C N Ganapathy
TRANSPORTV Jayaraman, In-charge
M K Raju Kutty
M Balarama
K Mohanan
G Prakash
Rahamath Pasha
G Raja
M Venkateshappa
AMENITIES(Guest House & Hostels)(Guest House & Hostels)(Guest House & Hostels)(Guest House & Hostels)(Guest House & Hostels)
Shivamallu
Mangala Singh
Muniratna
T Naganna
N Narayanappa (In charge)
D B Padmavathy
P C Prabhakar
N Puttaswamy
A Raju
N Seetharam
Uma
Sharadamma
Yashodha
HORTICULTUREBylappa
Govind K Kundagol
Lingegowda
D Mahalinga
Mailarappa
Marappa
D Muniraja
S Muniraju
Rahamathulla Khan
Rangalakshmi
Varalakshmi
MEDICALConsultant Paediatrician:Dr. M R Baliga
Consultant Physician:Dr. B V Sanjay Rao
Technician: R Shanthamma
CARPENTRYK M Lakshmanan(upto 30.6.2009)
M Gopinath
L Muthu
GAURIBIDANURTELESCOPESupport StaffSupport StaffSupport StaffSupport StaffSupport Staff
Bheema Naik
Gangaram
M Muniyappa
Papanna
N Raja Rao
R P Ramji Naik
Ranoji Rao
Shivarudraradhya
Thippanna
Venkataswamy
N R Srinath
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publications
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The institute publishes the researchactivities carried out over the year innational and international peer-reviewedjournals. Each of the four research groups atRRI finds their work published indistinguished journals that focus on theirspecific research area. For the TheoreticalPhysics group these include, but are notlimited to the Physical Review, Classical andQuantum Gravity, Journal of Physics, Journalof Statistical Mechanics and BiophysicsJournal. Research faculty and students fromthe Soft Condensed Matter group have theirwork published in journals like PhysicalReview, Liquid Crystals, Journal of PhysicalChemistry, Journal of Chemical Sciences,Journal of Applied Physics, EuropeanPhysical Journal, Journal of Nanoscience andNanotechnology and many more.Publications of the Light and Matter Physicsgroup at RRI can be found in PhysicalReview, Journal of Nanophotonics, OpticalExpress and Canadian Journal of Physics.The astronomers and astrophysicists at RRIuse the Physical Review, Monthly Notices ofthe Royal Astronomical Society, AstrophysicalJournal, the Journal of Astrophysics andAstronomy and others as a means to sharetheir work with the scientific communityaround the world. One hundred and sixteenpapers featuring RRI members as theirauthors and/or co-authors were publishedduring the year. There were 29 publicationsin conference proceedings and 26 (21 injournals and 5 in conference proceedings)publications are in press. Members at theinstitute expand and diversify their workbeyond the scope of highly specializedtechnical and science journals by publishingbooks and/or articles for popular sciencemagazines.
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other activitiesCONFERENCES
Conferences and visits to variousinstitutions at home and abroad play asignificant role in the research activities ofthe institute members. Such eventsprovide opportunities for idea exchangeand are often a starting point for futurefruitful collaborations with otherresearchers from various institutions withinIndia and abroad. Last year, faculty andstudents of the institute attendednumerous conferences in India, China,Australia, Brazil, Israel and all over Europe.In addition, lectures and invited talks weregiven at a variety of workshops,international programs, multinationalproject meetings and training programs.Members of the Institute visited collegesaround the country and speciallyorganized workshops on different scienceand research topics to deliver lectures, talkand presentations.
A full list of the conferences visited byeach of the institute members is providedin Appendix II.
SEMINARS AND COLLOQUIA
Thursday colloquia are one of thenumerous activities promoted at theInstitute as a way to increase theinteractions between the various researchgroups as well as RRI members and theinvited speaker and his/her institution.Apart from covering relevant sciencetopics, the colloquia often introduce newand interesting themes from various otherdisciplines.
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Last year, the institute invited speakers from allover India, USA, Australia, Canada and Europeto deliver the Thursday colloquia. Topics variedfrom “Cellular Journalism with DNA”, “Structureformation in the early Universe” and“Engineering of nanostructures” to “GlobalIndians: Negotiating identity in the softwareindustry” and “Gandhi, a man of the past or aman of the future?”.
A complete list of the speakers, their lecturetopics and when they visited RRI is given inAppendix III.
Seminars at the institute are often delivered bythe visiting faculty and researchers. Unlikecolloquia, seminars are intended to deepen theunderstanding and generate discussions on avery specific research theme. Usually, thetopics cover the current progress ofcollaborative projects between RRI and thevisitor’s institution, or themes of particularinterest to RRI members.
A list of the visiting research faculty andresearchers to RRI during the last year, is givenin Appendix IV.
VISITING SCHOLARS
A high priority is given to increasing the streamof visiting scholars to the institute. In today’shigh-tech world of global connectivity theacademic and research community is more
open then ever before. Maintaining nationallyand internationally open environment is crucialfor the success of every research institution.Members at RRI recognize that and worktirelessly toward creating more opportunitiesfor larger number of scientists, researchersand engineers to visit the institute, contributenew ideas and skills, while benefiting from theexpertise of our own members. Visits at RRIcan last from few days to few months andoften lead to important collaborative resultsand/or the conception of new interestingprojects.
Last year , there were more than 100 scholarswho visited RRI from 18 Indian and more than30 international institutions. RRI is happy tohave so many friends and thanks all of themfor making the environment in the institute sodiverse, dynamic and vibrant.
A list of all visitors, where they come from andwhen they visited RRI can be found inAppendix IV.
JOURNAL CLUB
The first meeting of the Journal Club was heldon Sept. 19th 1981 and with minorinterruptions its activities have continued up to
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date. The Journal Club at RRI aims at drawingthe attention of the institute members toexciting and interesting papers that appear inthe literature. Given the large numbers ofpapers published these days, it is nearlyimpossible for an individual to keep track ofdevelopments outside their researchspecialties. The Journal Club tries to partlyremedy this situation by presentations of avariety of recent papers of general interest.The last Journal Club slot of the year istraditionally reserved to review the year’sNobel Prize Award in Physics. While speakerspresent their selected papers, informaldiscussions, questions and demonstrations arestrongly encouraged as often they are theseeds of better understanding that can lead tobetter quality research.
A list of the papers reviewed during theJournal Club meetings last year is attached tothe annual report as Appendix V.
OTHERS
The RRI community is involved in various otheractivities ranging from organizing specialconferences, meetings and workshops, andinviting college students to the campus, to
having formal and informal dinners, sporttournaments, and a variety of culturalprograms both with invited performers ormembers of RRI itself. Such activities areconsidered to be an integral part of themembers’ experience at the institute.
Some of the major events that took place atRRI or were organized by some of its membersduring the last year are:
13 May 200913 May 200913 May 200913 May 200913 May 2009 – RRI hosted the awardceremony for the University of Sydney’sScience Foundation for Physics scholarships.The scholarships were given to 5 high schoolstudents to attend the 35th Harvey MesselInternational Science School scholarship. RRIfacilitated the selection of the Indian studentsfor this International event as part of itsoutreach activities, giving Indian students anopportunity to participate and showcase theirtalent in the International science school.
4 December 20094 December 20094 December 20094 December 20094 December 2009 – RRI was a participant inNIAS-RRI discussion meeting on “ClimateChange and Sustainable Living” which was heldat the National Institute of Advanced Studies(NIAS), Bangalore.
7–10 December 20097–10 December 20097–10 December 20097–10 December 20097–10 December 2009 – RRI organized andhosted the multinational Murchison Wide FieldArray project meeting.
30 January 2010 30 January 2010 30 January 2010 30 January 2010 30 January 2010 – Continuing the legacy of SirC V Raman, the institute invited Satish Kumarto deliver last year’s Gandhi Memorial Lecture.His profound life journey and his 8,000 milepeace pilgrimage (Satish Kumar walked from
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India to America without any money, throughdeserts, mountains, storms and snow) serve asinspiring examples of the power of noblehuman values.
8–19 F8–19 F8–19 F8–19 F8–19 February 2010 ebruary 2010 ebruary 2010 ebruary 2010 ebruary 2010 – RRI hosted the 11th
COSPAR Capacity Building Workshop. Theprincipal objective of the workshop was tointroduce young scientists to space basedGamma-ray astronomy and provide them with
training and experience on the analysis of datafrom the Fermi Gamma-ray Space Telescope.
7–19 Mar7–19 Mar7–19 Mar7–19 Mar7–19 March 2010ch 2010ch 2010ch 2010ch 2010 – RRI organized and hostedthe second RRI School on Statistical Physics.This was a pedagogical school, aimed atbridging the gap between masters-levelcourses and topics in statistical physics at thefront line of current research. It was intendedfor PhD students, post-doctoral fellows andinterested research faculty members at thecollege and university level. Courses from thearea of nonlinear dynamics and chaos, physicsof granular matter and nonequilibriumdynamics of quantum systems were offeredduring the school.
Numerous other events and activities includinga badminton tournament, in-house meetings,concerts, formal faculty farewell dinners,college visits and more continue to enrich anddiversify the academic life and atmosphere atthe Raman Research Institute.