program: center for optical sensors and spectroscopies...
TRANSCRIPT
http://http://www.coss.phy.uab.eduwww.coss.phy.uab.edu//Center for Optical Sciences and Center for Optical Sciences and SpectroscopiesSpectroscopies
Program: Center for Optical Program: Center for Optical Sensors and Sensors and SpectroscopiesSpectroscopies (COSS)(COSS)
Prepared by Dr. Chris Lawson (COSS Director, UAB)Dr. Sergey Mirov (COSS co-Director, UAB)Dr. Robert Pitt (co-PI, UA)Dr. Richard Fork (co-PI, UAH)Prepared forAlabama EPSCoR Annual Meeting, March 28-29, 2005
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UAB
UAHUA
COSS is a multi-institutional center(consisting of researchers and facilities from UAB, UA, and UAH)
COSS VISION The COSS center will be recognized nationally for excellence in lasers, optical sensors and spectroscopy addressing both education and research on environmental, biomedical, and
national security issues.
Laser-enabled optical sensor and spectroscopic technologies has had a significant impact all over the world on the major institutions in health care, biomedicine, communications, materials characterization and processing, defense, aerospace, environmental health, and national security, and this trend can only be expected to accelerate in the future.
COSS MISSIONCOSS MISSION
The mission of the COSS is to promote optical sensing and spectroscopy research on environmental, biomedical, and national security issues through collaborative use of resources and expertise among the member universities, government and industrial laboratories, and improve sensor techniques using recently developed revolutionary laser and spectroscopic technologies.
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The objective of the COSS is to utilize optical sensor technology used for detecting environmental contaminants and to improve these techniques using recently developed revolutionary laser and spectroscopic technologies.
One application will be Counter-Terrorism related applications such as the detection of chemical warfare agents and their precursors, explosive agents, and biological warfare agents
This capability will help to detect dangerous agents at the earliest possible stage (e.g., airport screening) before deployment by terrorists, and may avoid future chemical, biological, or radioactive terrorist attacks. This project could save thousands of lives.
Another application is to assist in emergency response to protect human health after natural disasters through the rapid detection of organic and inorganic toxicants.
The recent problems emphasized by Hurricane Katrina show that a rapid and efficient method to detect organic and inorganic toxicants in sediments and waters would be a very important tool to protect the public health of rescue workers and those responsible for rebuilding the devastated areas
What is the Purpose of the Center for Optical Sensors and Spectroscopies (COSS)?
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•areas
How optical spectroscopic sensing of toxins works. optical nose dog nose
Sniff. Automated intake sampling. Molecules above the solution are delivered into optical cell
Sensor-odor molecules interaction
Tunable laser radiation excites molecules in the cell
Inhaled volatiles are introduced to array of broadly specific receptor molecules
Signal Generation
Interaction of light with molecules gives rise to characteristic absorption spectra
Molecule-receptor binding generates series of action-potential patterns
Signal recognition
Potential patterns are relayed to the various layers of the olfactory bulb and these are passed on to higher level brain regions for identification
Smells like coffee
Odor identification
Absorption spectra are fed into a computer based spectrum recognition algorithm
Molecules identification and quantification
Sensitivity of the optical nose depends on linewidth, stability, and power of the pump laser, spectroscopic detection platform and noise reduction techniques and can be as good as sup-
parts per trillion, more than 100 times better than sensitivity of a dog nose.
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• The proposed Center, consisting of researchers from UAB, UA, and UAH will utilize current research strengths in Alabama, and combine them in a unique way to provide a completely new high technology capability for the state, and the development of shared research facilities that will provide crucial critical mass and infrastructure.
• One primary focus of the shared facilities is the upgrade of a multi-purpose facility for development of new optical spectroscopy laser sources
• Another focus will be centered around the purchase of a unique multipurpose COSS Cluster Spectroscopy System for ultra-sensitive detection of toxic materials, consisting of a confocal microscope system for Raman and photoluminescence spectroscopy, integrated with near field optical/atomic force microscopy system.
• In addition to the inherent capabilities of this system, a primary research focus on this proposal will be to increase its performance even further with a new ultra-fast CCD detection system, and by upgrading the laser sources with recently patented COSS Center laser technology.
COSS SHARED CORE FACILITIES
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UAB
UAH UA
GOAL 1: To create the infrastructure (core
spectroscopic research facility) for the collaborative
use of core facilities and specialized expertise in novel laser sources and
sensing of organic, inorganic and toxic agents.
GOAL 2: To foster important partnerships among research universities, national labs and industry of Alabama and nationwide.
GOAL 3: To strengthen research and graduate programs and human infrastructure at UAB, UA, and UAH.
GOAL 4: To Promote Minority/Under-
Represented Group Participation in COSS-Related Research and
Education
GOAL 5: To provide educational outreach for K12 students and teachers.GOAL 6: To effectively
manage and coordinate the COSS center
GOAL 7: To develop and characterize novel active and passive materials and light sources relevant for laser sensing, spectroscopic detection of organic, inorganic and toxic agents and counter-terrorism applications.
GOALS MILESTONES
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PROGRAM PLAN: 1. Upgrade Nd:YAG laser with optical parametric oscillator2. Upgrade DILOR XY microRaman system with NSOM/AFM option3. Upgrade DILOR XY microRaman system with ultrafast gated (80 ps) CCD camera (ICCD)PAYOFF: The upgraded system will provide us a unique capability for on-site, nondestructive
detection and characterization of explosives and biological, chemical and toxic substances.
Nd:YAG laser will be upgraded with the optical
parametric oscillator tunable over 0.4-2.7 µm
spectral range
Dilor XY microRaman System
Combining microRaman and FLIBS spectroscopy.Comparison of femtosecond produced plasma emission lines (left) or aluminum film and those obtained from a nanosecond formed plasma (right). The broad background emission is not present in the femtosecond case. This makes the detection of chemical and biological agents at low concentrations easier since the peaks come directly out of the baseline.
Combining scanning probe and Raman spectroscopy. Now Raman data can be recorded and correlated with high spatial resolution topographic, electrical, thermal and near-field optical data.
Goal 1:Goal 1: To create the infrastructure (core spectroscopic research facility) for the collaborative use of core facilities and specialized expertise in
novel laser sources and sensing of organic, inorganic and toxic agents.
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PROGRAM PLAN: To undertake joint university-industry, University –national or international labs projects
IndustryNational Labs
&Local centers
UAB
UAH UA
COSS Other EPSCoR Centers
International Collaboration
Goal 2:Goal 2: To foster important partnerships among research universities, national labs and industry of Alabama and nationwide
•Center for Environmental Cellular and Signal Transduction (CECST)
•Alabama Center for NanoTechnology Materials (ACNM)
•Extended Alabama Structural Biology Consortium (EASBC)
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Goal 2:Goal 2: To foster important partnerships among research universities, national labs and industry of Alabama, and nationwide.
Ion ImplantationManufacture p-n junctions in ZnSe
Quantum Dot formation
Color Center formation (Auburn Nuclear Center)
Our Goals
Produce first electrically pumped RT, broadly tunable Mid-IR laser
Produce new quantum dot based Cr2+:ZnS and Cr2+:ZnSe lasers
Laser Crystal Preparation
Collaboration
ACNM
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Goal 2:Goal 2: To foster important partnerships among research universities, national labs and industry of Alabama, and nationwide.
EASBC/CBSE
Design Space Grade Optical Nose
Design and Analysis Tools
Engineer pathogen selective antibodies for “Sensing through the walls”
COSS
Characterize protein crystal quality with MicroRaman facility.
Build laser spectrometer for optical nose.
“Sensing through the walls” novel methods of selective excitation and detection through walls of signals from nanowires attached to pathogens.
Collaboration
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Goal 3:Goal 3: To strengthen research and graduate programs and human infrastructure at UAB, UA, and UAH.
Recruit new faculty and outstanding graduate students :
two research assistant professors at UAB
faculty member with expertise in biosensors (UAB)
faculty with expertise in urban infrastructure
Advertise UAB, UAH and UA graduate programs in lasers, spectroscopy and environmental science nationally
Offer specialized and advanced courses to graduate students :
Two semester series in Laser Physics, Laser Spectroscopy, nanomaterialsWorkshops, in Stormwater management, Construction site erosion control, International urban water infrastructured, Effects and fates of hazardous materials
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Goal 3:Goal 3: To strengthen research and graduate programs and human infrastructure at UAB, UA, and UAH
Obtain non-EPSCoR funding
1. NSF impurity doped quantum confined II-VI structures for electrical pumping of mid-IR lasers –funded
2. NSF Laser optical nose - funded3. NIH, early optical nose diagnostics of lung cancer - submitted4. DARPA, sensing biological pathogens through the wall - submitted5. ARL proposal for sensor protection - submitted6. NIH proposal on Imaging guided interventions - submitted7. NSF proposal on environmental sampling after natural disasters8. EPA proposal on small community water quality monitoring efforts9. NIH proposal on international environmental health education
initiatives10. Research and royalty Agreements with Industrial Collaborators and
financing through Venture Capitalists.
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Lawrence Luke summer 2005 REU program. Studied novel mid-IR laser materials at COSSPROGRAM PLAN:
1. Implement NSF-funded REU (UAB physics) at COSS 2. Implement Bridge for Doctorate program at UAB and UAH3. Implement EMAP minority summer program at UA
COSS center takes part in the EPSCoR/LSAMP summer research conference, July 22, 2005.
New UAB physics graduate fellow Ms. Hadiyah Green sponsored by UAB Bridge for Doctorate Program with her mentor Dr. S.Mirov, COSS Co-Director
Goal 4:Goal 4: To Promote Minority/Under-Represented Group Participation in COSS-Related Research and Education
Ms. Clarissa Byrd presents a talk on Optical Detection of Atmospheric Contaminants. Mentor –Dr. R.Fork, UAH COSS member
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Goal 5:Goal 5: To provide educational outreach for K12 students and teachers.
NSF- Research Experiences for Teachers
•Recruit high school teachers for training at COSS via NSF-funded RET program (UAB physics).
•Coordinate educational outreach at schools with Science in Motion Program (UAB) at UAB and UAH.•Develop new experiments for science in motion program.
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PROGRAM PLAN: 1. Provide effective oversight of the COSS center
1. Hold yearly meetings with the external advisory board committee2. Hold quarterly management meetings (meetings or teleconferences)3. Submit quarterly reports to the Alabama EPSCoR 4. Hold periodic scientific meetings or teleconferences for co-investigators5. Monthly budget reviews
2. Monitor individual project/task status through quarterly status reports and website3. To inform general public and EPSCoR Office on COSS activities through website, press releases
UAB
UAH
UA
Alabama EPSCoR Steering CommitteeAlabama EPSCoR
Steering Committee
Goal 6:Goal 6: To effectively manage and coordinate the COSS center
Advisory Board Committee
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Goal 7:Goal 7: To develop and characterize novel active and passive materials aTo develop and characterize novel active and passive materials and light nd light sources relevant for laser sensing, spectroscopic detection of osources relevant for laser sensing, spectroscopic detection of organic, inorganic rganic, inorganic
and toxic agents and counterand toxic agents and counter--terrorism applicationsterrorism applications.
I. Development and characterization of novel active and passive optical materials for optical sensor technology
II. Development of light sources relevant to spectroscopic applications
III. Development of laser spectroscopic systems for detecting environmental contaminants and Counter-Terrorism related applications
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I.I. Development and characterization of novel active and passive optical materials for optical sensor technology
Development of II-VI laser materials Diffusion doping of TM ionsLaser Ceramic MaterialsQuantum dot and quantum well laser structuresThin Film Preparation and Characterization
Pay off: Fabrication of the first electrically pumped RT, broadly tunable Mid-IR laser
ZnS
Si
ZnS
Si
5 µm
ZnS
CBA
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II. Development of light sources relevant to spectroscopic applications
Compact fiber laser pumped Er:YAG and Ho:YAG lasersRoom temperature lasers tunable in MIR spectral region
Pay off: Development of heat-seeking missile countermeasures. Lasers for Mid-IR sensing.
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I. Development and characterization of novel active and passive optical materials for optical sensor technology Development of II-VI laser materials by diffusion doping of TM ions
Crystals were synthesized by Crystals were synthesized by CVT using iodine as transport CVT using iodine as transport agent ( C(Iagent ( C(I22)=2)=2--5 mg/cm5 mg/cm3 3 ))Ampoule size: Ampoule size: ∅∅20mm x 20mm x 200mm200mmTemperature range 1200Temperature range 1200ooC C --11001100ooCC
P=10P=10--55 torr torr T= 1000 C T= 1000 C t=7t=7--20 days20 days
Pulsed laser Pulsed laser depositiondeposition
Thermal annealingThermal annealing
The polished samples of The polished samples of 11--2 mm thickness and up 2 mm thickness and up to 5 mm in aperture were to 5 mm in aperture were used for spectroscopic used for spectroscopic and laser measurementsand laser measurements
Chromium thin Chromium thin film deposition film deposition on the crystals on the crystals wafer by means wafer by means of pulsed laser of pulsed laser deposition deposition methodmethod
Chemical Vapor Chemical Vapor Transport (CVT)Transport (CVT)
Crystal
PowderCr
Crystal
Crystalλ=532 nm
E=500 mJZnS+I2↔ ZnI2+1/2S2
Mirov, Fedorov, US Patent 6,940,486 November 2005
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I. Development and characterization of novel active and passive optical materials for optical sensor technology
Novel Co:ZnS passive bulk material
Saturation at 731nm
Photon Flux(mJ/cm2)
0 100 200 300 400 500 600 700 800
Tran
smis
sion
0.0
0.2
0.4
0.6
0.8
1.0
Q-Switch
time, us
0 20 40 60 80 100
V
0.0
0.5
1.0
1.5
2.0
2.5
3.0
Lamp
Alexandrite crystalFilter Liot
Rout=50% R=100%
Power Meter
Oscilloscope
Wavemeter
Photodiode
ZnS:Co:Cr
time, ns0 50 100 150 200 250 300 350 400
0
1
2
Q-switching of alexandrite laser was achieved with ZnS:Co:Cr at 754nm with a pulse duration of approximately 50 ns and 15mJ of energy.
R.A.Sims, et al, Photonics West 2006.
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I. Development and characterization of novel active and passive optical materials for optical sensor technology
Development of II-VI ceramic laser materials
A fabrication process of optical material based on hot-pressed Cr2+:ZnSe ceramic with optical quality sufficient for the first everdemonstration of gain-switched lasing in such a material was made.
ZnSe+ CrSe(0.1-0.01%)
ZnSe
P=60MPa
ZnSe+ CrSe(1%) ∅15 mm
P=30-350MPa
CLEO’05
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I. Development and characterization of novel active and passive optical materials for optical sensor technology
Development of II-VI ceramic laser materials
The laser yielded 2 mJ of output energy at a slope efficiency up to 5%. Further investigations are needed for developing of hot-pressed samples with high optical density (αmax=5-10 cm-1 at 1.8 µm) and low losses. The presented results demonstrate the first proof of the feasibility of the mid-IR laser systems based on hot-pressed ceramic. Further technological advances are needed to decrease the passive loss of hot-pressed ceramics to achieve large impact factors of ceramics on the synthesis of large-scale mid-IR laser media.
Abs. Energy (mJ)0 10 20 30 40 50 60
Out
put E
nerg
y (m
J)
0
1
2
BCA
η=3%η=5%η=8%
CLEO’05
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I. Development and characterization of novel active and passive optical materials for optical sensor technology
Development of II-VI thin film laser materials
SEM surface (C) and cross section (A,B) images of Cr doped ZnS thin film with thickness 12 µm and cross section (B,C) and 200 nm ZnS thin films (A)
Schematic of integrated PLD facility
µs4 6 8
Sig
nal (
a.u.
)
0.1
1
AThin Film
Bulk
300K
20K23K
300K
Luminescence life time measurements of bulk and thin film samples at 300K and ~20K.
Face
Edge
Bulk
Constructive InterferenceDestructive Interference
Plots of the luminescence spectra of a thin film sample in different geometries and a bulk sample for comparison.
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I. Development and characterization of novel active and passive optical materials for optical sensor technology
Mid-IR Luminescence of ZnS nanoparticles
A
Wavelength, nm2500 3000 3500 4000 4500 5000
0
2
4
6
8
10
12
14
B
time, µs
0 50 100 150 200
Intensity, a.u.
0.01
0.1
Mid-IR photoluminescence spectra of chromium doped annealed ZnS nanoparticles; B- Kinetics of fluorescence measured at 2-5 µm spectral range
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I. Development and characterization of novel active and passive optical materials for optical sensor technology Novel TM:II-VI materials
1.The first Co:ZnSe passive Q-switch was developed for 745nm. (Photonics West 2006)
2.The first hot pressed Cr:ZnSe samples showed gain switched lasing (CLEO 2005)• These results as well as the continuing research in TM:ZnSe materials allow us to
continue leading the field in solid state photonics research.
We developed techniques for providing thermal diffusion for variWe developed techniques for providing thermal diffusion for various transition metal doping in IIous transition metal doping in II--VI VI materials.materials.
We are developing techniques to produce PLD grown thin films of We are developing techniques to produce PLD grown thin films of ZnSe doped with Chromium for ZnSe doped with Chromium for future research in electrically pumped future research in electrically pumped pp--nn junction based laser systems.junction based laser systems.
We are developing techniques to produce solWe are developing techniques to produce sol--gel grown quantum dots of ZnSe doped with gel grown quantum dots of ZnSe doped with ChromiumChromium
1. A. Gallian, V. V. Fedorov, S. B. Mirov, V. V. Badikov, S. N. Galkin, E. F. Voronkin, A. I. Lalayants, “Hot-Pressed Ceramic Cr2+:ZnSe Gain- Switched Laser”, CLEO, Baltimore, Maryland, May 22-27 2005
2. A. Gallian, V. V. Fedorov, J. Kernal, J. Allman, S. Mirov, E. M. Dianov, A. O. Zabezhaylov, I. P. Kazakov “En Route to Electrically Pumpable Cr2+ Doped II-VI Semiconductor Lasers” , ASSP, Vienna, Austria, Feb 6-9 2005
3. A.R. Gallian, V.V. Fedorov, J. Kernal, J. Allman, S.B. Mirov, E. Dianov, A. Zabezhaylov, I. Kazakov“Photoluminescence studies of MBE grown thin films and bulk Cr:ZnSe”, SESAPS, Oakridge, TN, Nov 11-13 2004
time, ns0 50 100 150 200 250 300 350 400
0
1
2
Co:ZnSe Q-Switch
Ceramic Cr:ZnSe
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II. Development of light sources relevant to spectroscopic applications.
Tm fiber laser pumped Ho:YAG laser
Output power of CW and 10kHz Q-switched Ho:YAG laser vs pump power.
CW and 10 kHz Q-switched with 50% OC
Pump power, W2 4 6 8 10 12 14 16 18 20 22 24
Out
put p
ower
, W
0
2
4
6
8
10CW QS, 10 kHz
The maximum achieved output energy was 15 mJ at 100Hz repletion rate with sustained damage free operation of the laser. Experiments show that at 25 W of pump power up to 25 mJ of output energy is achievable.
The Ho:YAG laser operated in the Q-switched regime at 50 Hz-10 kHz repetition rates. The minimum pulse duration was 17 ns at 100 Hz and increased to 20 ns at repetition rate of 1000 Hz.
ASSP’06
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Lasing of Cr2+:ZnSe via Ionization Transitions (ASSP’05)
µs0 2 4 6 8
mV
0
5
10
15
20
25
0 2 4
Pump Pulse
Lasing from 532nm pumping
Lasing from 1560nm pumping
µs
Build up time
Lasing from 532nm pumping
Pump Energy, mJ5 10 15
Lasi
ng In
tens
ity, a
b.un
.
0
5
10
15
20
25
wavelength, nm1800 2000 2200 2400 2600 2800 30000
1
Inte
nsity
, ab.
un.
Lasing from 532nm pumping
Luminescence from 532nm pumping
Lasing and Luminescence spectrum under 532nm excitation
Lasing output
intensity
versus pump
energy
ZnSe CB
VB
Eac
Ed
Cr2+/Cr+
Time+ +
hνpump
hνos
Cr2+*
5E
5T2
Cr2+*
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Mid-IR Electroluminescence of n-Cr:ZnSe (ASSP’06 WB21)Absorption Spectra Al:Cr:ZnSe
K (cm
-1)
0
2
4
6
8
Wavelength (nm)1200 1600 1800 2000
I-V Curves for Cr-Al:ZnSe Samples # 1 & 2
Voltage(V)-80 -60 -40 -20 0 20 40 60 80
Cur
rent
(mA
)
-10-8-6-4-2
246810
Sample#2
Sample#10
~30KΩ
~7.5KΩ
Time (µs)-200 0
Vol
ts
-2
mid-IR optical signal
Electrical pulse
200
-4
Visible Luminescence ofVZn-Al complex
Inte
nsity
, a.u
.
mid-IR Cr2+ electroluminescence
Wavelength (nm)
Inte
nsity
, a.u
.
Wavelength (nm)400 600 800 1800 2200 2600
Cr2+ optical pumping
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RT Fe:ZnSe Lasing in Nonselective cavityRT Fe:ZnSe Lasing in Nonselective cavity
B
Pump Energy, mJ/cm2
50 100 150
Sign
al, a
.u.
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4Ai - 40mJ/cm2
ii -110 mJ/cm2
iii-170 mJ/cm2
wavelength, nm
3750 4000 4250 4500 4750 5000
Sign
al, a
.u.
i
ii
iii
Emission spectra of Fe:ZnSe crystal versus pump density; B- Output of RT gain-switched Fe:ZnSe lasing in nonselective cavity versus pump
density
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RT Fe:ZnSe Lasing in RT Fe:ZnSe Lasing in LittrowLittrow Cavity Cavity
wavelength, nm
3800 4000 4200 4400 4600 4800
Lase
r out
put ,
a.u
.
0.0
0.2
0.4
0.6
0.8
1.0
i
ii
Tuning curve of RT gain-switched Fe:ZnSe laser (i) and example of oscillation spectrum at 4490 nm (ii)
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wavelength, nm3800 4000 4200 4400 4600 4800
Lase
r out
put ,
a.u
.
0.0
0.2
0.4
0.6
0.8
1.0
II. Development of light sources relevant to spectroscopic applications. Novel Mid-IR Tunable Lasers
B
wavelength, nm1600 1800 2000 2200 2400 2600 2800
Inte
nsity
, a.u
.
(II)(I)
We demonstrated, for the first time ever, an observation of lumiWe demonstrated, for the first time ever, an observation of luminescence under electrical nescence under electrical excitation from chromiumexcitation from chromium--doped ndoped n--type ZnSetype ZnSeWe developed high optical density and high quality Fe:ZnSe crystWe developed high optical density and high quality Fe:ZnSe crystals and demonstrate the als and demonstrate the feasibility of Fe:ZnSe crystals for gainfeasibility of Fe:ZnSe crystals for gain--switched lasing at room temperature (RT).switched lasing at room temperature (RT).We demonstrated the first room temperature gainWe demonstrated the first room temperature gain--switched tunable oscillation of Fe:ZnSe switched tunable oscillation of Fe:ZnSe crystal over 3.9crystal over 3.9--4.8 4.8 µµm spectral range.m spectral range.Ten reports, Ten reports, 12 articles/proceedings, one book chapter, and one patent12 articles/proceedings, one book chapter, and one patent have been have been students and researchers from the COSS center at UAB.students and researchers from the COSS center at UAB. One PhD dissertation has been One PhD dissertation has been successfully defended.successfully defended.
1. J. Kernal, V. V. Fedorov, A. Gallian, S. B. Mirov, and V. V. Badikov,"3.9-4.8 µm gain-switched lasing of Fe:ZnSe at room temperature“, Optics Express, V. 13, p. 10608, (2005)
2. Fedorov, J. Kernal, A. Gallian, S. B. Mirov, V. V. Badikov “3.9-4.8 µm gain-switched lasing of Fe:ZnSe at room temperature”, Photonics West Conference/ SOLID STATE LASERS XV [6100-13], (2006)
3. L. Luke, V. V. Fedorov, I. S. Moskalev, A. Gallian, S. B. Mirov, “Middle-infrared electroluminescence of n-type Cr doped ZnSe crystals, Photonics West Conference/ SOLID STATE LASERS XV [6100-26], (2006)
1) The first optically pumped chip-scale laser operating at room temperature in the window of atmospheric transparency over 3.9-4.8 um spectral range has been realized.
2) The first middle-infrared (2-3mm) electroluminescence of chromium doped ZnSe has been demonstrated.
Both results represent novel approach in laser physics - laser oscillation occurs under optical or electrical excitation due to electron transitions within the Cr and Fe impurity incorporated into semiconductor crystal.
This approach enables a new pathway for ultrasensitive miniature mid-IR sensors having significant technological relevance for: detection of explosives, chemical and biological warfare agents; industrial process control; biomedical applications, i.e. detecting markers associated with malignant tissues and measurement of medically important molecular compounds in the exhaled breath of patients; many other industrial and scientific applications.
IR lasing of Fe:ZnSe
Electroluminescence of Cr:ZnSe
http://http://www.coss.phy.uab.eduwww.coss.phy.uab.edu//Center for Optical Sciences and Center for Optical Sciences and SpectroscopiesSpectroscopies
Dilor XY microRaman System
There is a great need for:
•Minimization of sample preparation•Maintenance of high sensitivity•Nearly real-time results
Colloidal metallic nanoparticles prepared by laser ablation and MethophotonicsKlariteTM SERS substrate
SERS spectrum of PAHs challenging sample prepared by using traceable standard materials
Advantages of SERS:
• Minimal sample preparation required• High sensitivity to specific compounds• Real time measurements (less than afew minutes)
• Challenging multicomponent samplesanalysis
• Infield detection and characterization of environmental pollutants are possible
III. Develop laser system for detecting environmental contaminants Department of Physics at UAB and Department of Civil and Environmental Engineering at UA teams developing a new technique based on Surface Enhanced Raman Spectroscopy (SERS) for rapid identification of polycyclic aromatic hydrocarbons (PAHs), pesticides and herbicides pollutants
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Researchers at UA Environmental Institute have prepared test samples and performance objectives for the new optical spectroscopic measurement instrumentation.
Challenge samples are being obtained and parallel tested to measure the actual performance of the laser instruments.
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Absorption spectra of silver and gold colloidal metal nanoparticles prepared by laser ablation method.
Silver and gold colloidal metal nanoparticles prepared by laser ablation method.
Metal wire
Ar In Ar Out
Pulsed laser light
Schematic diagram of laser ablation method. Pulsed laser light is focused on silver or gold wire placed in double distilled water under continues degassing by argon.
The advantage of laser ablation is absence of chemical reagents in solutions comparing to other conventional method for preparing metal colloids. Therefore pure colloids are produced and being used in UAB Laser laboratory for surface enhanced Raman spectroscopy (SERS).
Various laser conditions such as wavelength, energy and pulse duration effect average particle size and shape, which can be adjusted in controllable manner.
Preparation of colloidal metal nanoparticles by laser ablation.
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Core. Water n=1.33
Cladding. Teflon ® AF 2400 n=1.29
Laser light
10+ miters
To Raman spectrometer
The alternative approach is use of liquid waveguide capillary cell (LWCC). Capillary tube made of commercialavailable polymer Teflon-AF 2400 with refractive index 1.29 filled up with water acts as liquid core waveguidTeflon-AF 2400 is transparent in 200-2000nm spectral region therefore Vis light coupled into such a waveguidcould propagate to a significant distance. This will allow to increase weak Raman signal by several orders magnitude.
Liquid Waveguide Capillary Cell (LWCC).
http://http://www.coss.phy.uab.eduwww.coss.phy.uab.edu//Center for Optical Sciences and Center for Optical Sciences and SpectroscopiesSpectroscopies
5x10-3
4
3
2
1
Abs
orba
nce
440435430425420415Wavelength /nm
W aveleng th ,nm 1038 1039 1040 1041 1042
Opt
ical
Den
sity
505 510 515
Wavelength, nm505 510 515505 510 515
Inte
nsity
, arb
.un
0
10000
20000
30000
40000
50000
60000
70000RO water Distilled water Cu - 10 µg/l
CuCu
Cu
3ω (2
nd o
rder
)
3ω (2
nd o
rder
)
3ω (2
nd o
rder
)
Example of sensitive LAF detection of Cu atoms in water sample (Cu-10µg/L), distilled water, and deionized water
LensLens
SpectrographARC-750
CCD
PC
Sample(in graphite furnace)
HV Pulse GeneratorPG-200
Aperture
FiberGuide
Tunable UVlaser
LASER ATOMIC FLUORESCENCE SPECTROSCOPYPersistent photon-gated spectral hole burning in
LiF:F2- color center crystal
EVANESCENT CAVITY RING-DOWN SPECTROSCOPY (E-CRDS) OF HEMOGLOBIN
ABSORPTION
⎟⎠⎞
⎜⎝⎛∆
=20
rtAbsτττ
III. Develop laser system for detecting environmental contaminants and Counter-Terrorism related applications
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Cr2+:ZnSe/CdSe/ZnS Single Frequency Tunable laser 2-3.5 µm
Diode pumped Tm fiber laser
Amplifier
Ho:YLF AOM
ZGP CdSe
OPG-OPA
Cr2+:II-VI SLM injection seeder Diode pumped Tm fiber laser
Absorption cell
Reference absorpber
Set of etalons
Power meter
FMSdetector
Gas inlet Detection & Calibration
• By rapidly tuning the wavelength of the OPG, the absorption of a gas mixture is measured as a function of the wavelength.
• The instrument will be capable of identifying a large variety of molecular organic trace-gases in multi-compound gas-mixtures and to quantify them at ultra-low concentration levels.
• The proposed instrument will provide a complete, total profile of the trace gas contents in complex gas mixtures in real-time, i.e. with response times in the order of seconds.
Exhaled Gas Sample
Diode pumped Er fiber laser
Diode pumped Er-fiber laser
Er:YAG
III. Develop laser system for detecting environmental contaminants and Counter-Terrorism related applications. Middle-IR Optical nose
http://http://www.coss.phy.uab.eduwww.coss.phy.uab.edu//Center for Optical Sciences and Center for Optical Sciences and SpectroscopiesSpectroscopies
COSS Researchers are currently developing Optical Power Limiting (OPL) technology for protection against wavelength tunable laser threats
• Another research area of the Center for Optical Sensors and Spectroscopies is the PROTECTION of optical sensors and eyes
• In December of 2004, The FBI and Department of Homeland Security sent out a memo warning that there is evidence that terrorists have explored using lasers as weapons to bring down commercial airliners
http://http://www.coss.phy.uab.eduwww.coss.phy.uab.edu//Center for Optical Sciences and Center for Optical Sciences and SpectroscopiesSpectroscopies
Chemical Structure of[(R-APPC)M]Cln Complexes
n+
N M
NN
NN
R
nCl
L
L
Theoretical and Experimental Studies of Excited State Absorbers
for Optical Power Limiting
PI: Chris Lawson, University of Alabama atBirmingham, [email protected]
RESEARCH GOAL: Develop new metal-organic complexes for power limiting applications, and study the relationship between chemical structure and optical nonlinearity in these complexes.
Expanded porphyrin complexes[(R-APPC)M]Cln (most promising yet)• Extensively delocalized π-conjugated
electron system (18-26 π electrons)• Broad region of low linear absorption
(480-660 nm)• High third order optical nonlinearities• Remarkable chemical and thermal
stability• Exhibit strong optical limiting via
reverse saturable absorption for nspulses, 532 nm.
• Easily-modified chemical structure- Can vary R group- Large variety of candidate metals, M- Many candidate axial ligands, L
(NC)2C2-CdTXP
Incident Fluence (J/cm2)
0.001 0.01 0.1 1 10
Tran
smitt
ance
0.0
0.1
0.2
0.3
0.4
0.5
0.6
experimental (5 ns)experimental (40 ps)theoretical (5 ns)theoretical (40 ps)
M. McKerns, W. Sun, C. Lawson, andG. Gray, “Higher-order triplet-triplet interaction in energy-level modeling of excited-state absorption for an expanded porphyrin cadmium complex”, accepted for publication, J. Opt. Soc. Am. B, 2004.
and
C. Byeon, et al., Appl. Phys. Lett. 84,5174 - 5176 (2004).
T1
T2
Tn
Sn
S2
S1
S0
10k
21k
42k
65k
53k
01σ
12σ
24σ56σ
35σ
30k
13k
25k
RECENT WORK:• Using 7-level theoretical model of nonlinear absorption to fit both ns and ps optical limiting data allows us to extract excited-state lifetimes and absorption cross-sections in expanded porphyrin complexes, and track population over duration of the excitation pulse. Increased knowledge of these complexes leads to appropriate changes in chemical structure and better optical limiting.• Currently carrying out synthesis of new expanded porphyrin materials with Cd, Ag and other metal centers and various axial ligands.
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Journal Articles and Published Proceedings (2005-2006)1. A. Gallian, V. V. Fedorov, J. Kernal, J. Allman, S. B. Mirov, E. M. Dianov, A. O. Zabezhaylov, I. P. Kazakov, “Spectroscopic studies of
molecular-beam epitaxially grown Cr2+ -doped ZnSe thin films” Applied Physics Letters, v.86, 091105, (2005)2. A. Gallian, V. V. Fedorov, J. Kernal, S. B. Mirov, V. V. Badikov “Laser Oscillation at 2.4 µm from Cr2+ in ZnSe Optically Pumped over Cr
Ionization Transitions” in Advanced Solid-State Photonics 2005 Technical Digest on CD-ROM (The Optical Society of America, Washington, DC, 2005), MB12
3. A. Gallian , V. V. Fedorov, J. Kernal, J. Allman, S. Mirov, E. M. Dianov, A. O. Zabezhaylov, I. P. Kazakov,” En Route to Electrically Pumpable Cr2+ Doped II-VI Semiconductor Lasers” in Advanced Solid-State Photonics 2005 Technical Digest on CD-ROM (The Optical Society of America, Washington, DC, 2005), TuB14
4. I. S. Moskalev, V. V. Fedorov, S. B. Mirov, “Multiwavelength Mid-IR Spatially-Dispersive CW Laser Based on Polycrystalline Cr2+: ZnSe”, in Advanced Solid-State Photonics 2005 Technical Digest on CD-ROM (The Optical Society of America, Washington, DC, 2005), TuB12
5. A.G. Van Engen Spivey, V. V. Fedorov, S. B. Mirov, and Ch. M. Lawson “Amplification of narrow line LiF:F2+** color center laser oscillation”, Optics Communications, Volume 254 , Issues4-6 , Pages290-298 (2005)
6. J. Kernal, V. V. Fedorov, A. Gallian, S. B. Mirov, V. V. Badikov,”3.9-4.8 µm gain-switched lasing of Fe:ZnSe at room temperature”, Optics Express, Vol. 13, No. 26, pp. 10608 – 10615, (2005)
7. T.T. Basiev, M.N. Basieva, M.E. Doroshenko, V.V. Fedorov, V.V. Osiko, S.B. Mirov, “Stimulated Raman scattering in mid IR spectral range 2.31-2.75-3.7 µm in BaWO4 crystal under 1.9 and 1.56 µm pumping” Laser Physics Letters, Volume 3, pp17-20, (2006)
8. V. V. Fedorov, J. Kernal, A. Gallian, V. V. Badikov, S. B. Mirov, ”3.9-4.8 µm gain-switched lasing of Fe:ZnSe at room temperature,” in Solid State Lasers XV: Technology And Devices, Proceedings of SPIE 6100, San Jose, California USA, 21–26 January, (2006).
9. V.V. Fedorov, I. Moskalev, L. Luke, A. Gallian, S.B. Mirov ”Mid-infrared Electroluminescence of Cr2+ Ions in ZnSe Crystals” , in Advanced Solid-State Photonics 2006, WB21, Technical Digest on CD-ROM (The Optical Society of America, Washington, DC, 2006)
10. J. Kernal, V. Fedorov, A. Gallian, S. Mirov, V. Badikov, "Room Temperature 3.9-4.5 µm Gain-Switched Lasing of Fe:ZnSe", in Advanced Solid-State Photonics 2006, MD6, Technical Digest on CD-ROM (The Optical Society of America, Washington, DC, 2006)
11. I. S. Moskalev, V.V. Fedorov , S.B. Mirov,A.Babushkin, V.P.Gapontsev, D.V.Gapontsev, N.Platonov, "Efficient Ho:YAG Laser Resonantly Pumped by Tm-Fiber Laser", in Advanced Solid-State Photonics 2006, TuB10, Technical Digest on CD-ROM (The Optical Society of America, Washington, DC, 2006)
12. T. Basiev, M. N. Basieva, M. E. Doroshenko, V. V. Fedorov, V. V. Osiko1, S. B. Mirov,"Stimulated Raman Scattering in the Mid IR Range 2.31-2.75-3.7 µm in a BaWO4 Crystal under 1.9 and 1.56 µm Pumping", in Advanced Solid-State Photonics 2006, MB10, Technical Digest on CD-ROM (The Optical Society of America, Washington, DC, 2006)
13. Marquecho, R. and R. Pitt (2005). “Metal Associations with Stormwater Particulates,” 78th Annual Water Environment Federation Technical Exposition and Conference. Washington, D.C. Oct. 29 – Nov. 2, 2005.
14. Pitt, R., A. Maestre, and R. Morquecho. “A National Stormwater Quality Database, part 1,” invited feature article. Watershed/Wet Weather Technical Bulletin, Water Environment Federation. 2005.
15. Pitt, R. and A. Maestre. “A National Stormwater Quality Database, part 2,” invited feature article. Watershed/Wet Weather Technical Bulletin, Water Environment Federation. 2005.
16. Clark, S., M.M. Lalor, and R. Pitt. “Wet-weather pollution from commonly-used building materials.” World Water and Environmental Resources Congress. ASCE/EWRI. Anchorage, Alaska. May 2005. (conference CD-ROM).
17. Pratap, M., U. Khambhammettu, S. Clark, and R. Pitt. “Stormwater treatment using upflow filters.” World Water and Environmental Resources Congress. ASCE/EWRI. Anchorage, Alaska. May 2005. (conference CD-ROM).
18. Morquecho, R. and R. Pitt. “Pollutant associations with particulates in stormwater.” World Water and Environmental Resources Congress. ASCE/EWRI. Anchorage, Alaska. May 2005. (conference CD-ROM).
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Chapters in Books (2005-2006)
1. I.S.Moskalev, V.V.Fedorov, T.T.Basiev, P.G.Zverev, S.B.Mirov, "Application of laser beam shaping for spectral control of "spatially dispersive" lasers" in Laser Beam Shaping Applications, Dickey, Holswade, Shealy - Eds., Marcel & Dekker ISBN: 0824759419, (2005).
2. Maestre, A. and R. Pitt. “Observations from the National Stormwater Quality Database.” In: Stormwater and Urban Water Systems Modeling, Monograph 14. (edited by W. James, K.N. Irvine, E.A. McBean, and R.E. Pitt). CHI. Guelph, Ontario, to be published in 2006.
3. Clark, S.E., R. Pitt, P.D. Johnson, S. Gill, and M. Pratap. “Media filtration to remove solids and associated pollutants from stormwater runoff.” Best Management Practices (BMP) Technology Symposium: Current and Future Directions, American Society of Civil Engineers. 2005.
4. Maestre, A., R. Pitt, S.R. Durrans, and S. Chakraborti. “Stormwater quality descriptions using the three parameter lognormal distribution.” Effective Modeling of Urban Water Systems, Monograph 13. (edited by W. James, K.N. Irvine, E.A. McBean, and R.E. Pitt). CHI. Guelph, Ontario, pp. 247 – 274. 2005.
5. Pitt, R., R. Bannerman, S. Clark, and D. Williamson. “Sources of pollutants in urban areas (Part 1) – Older monitoring projects.” In: Effective Modeling of Urban Water Systems, Monograph 13. (edited by W. James, K.N. Irvine, E.A. McBean, and R.E. Pitt). CHI. Guelph, Ontario, pp. 465 – 484 and 507 – 530. 2005.
6. Pitt, R., R. Bannerman, S. Clark, and D. Williamson. “Sources of pollutants in urban areas (Part 2) – Recent sheetflow monitoring results.” In: Effective Modeling of Urban Water Systems, Monograph 13. (edited by W. James, K.N. Irvine, E.A. McBean, and R.E. Pitt). CHI. Guelph, Ontario, pp. 485 – 530. 2005.
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Conference presentations (2005-2006)1. A. Gallian, V.V. Fedorov, Sergey B. Mirov, V. V. Badikov, S. N. Galkin, E. F. Voronkin, A. I. Lalayants “Hot-Pressed Ceramic
Cr2+:ZnSe Gain-Switched Laser,” in Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science and Photonic Applications, Systems and Technologies 2005 (Optical Society of America, Washington, DC, 2005), CME6.
2. A. Gallian, V.V. Fedorov, I. S. Moskalev, Sergey B. Mirov, V. V. Badikov, “Cr2+:ZnSe Laser Pumped over Cr Ionization Transitions,” in Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science and Photonic Applications, Systems and Technologies 2005 (Optical Society of America, Washington, DC, 2005), CTuA4.
3. A.Gallian, V.V.Fedorov, I.S. Moskalev, S.B.Mirov, V.V. Badikov “Cr2+:ZnSe Laser Pumped Utilizing Cr Ionization”, International Conference on Coherent and Nonlinear Optics and International Conference on Lasers, Applications, and Technologies (ICONO/LAT) , St. Petersburg, Russia, May 11-15, (2005).
4. S. B. Mirov, V. V. Fedorov, J. Kernal, A. Gallian, V. V. Badikov, “3.9-4.5 µm gain-switched lasing of Fe:ZnSe at room temperature”Mid-Infrared Coherent Sources Conference , Barcelona (Spain) 6-11 November (2005).
5. J. Allman, A.O. Zabezhaylov, E.M. Dianov, I.P. Kazakov, S.B. Mirov, V.V. Fedorov, A. Gallian, J.Kernal, ” MBE Growth and study of Cr2+:ZnSe Layers for Mid-IR Lasers”, 13th Int. Symp. “Nanostructures: Physics and Technology” , St Petersburg, Russia, June 20–25, (2005).
6. I.S. Moskalev, V.V. Fedorov, S.B. Mirov , “Multiwavelength, ultrabroadband semiconductor and solid-state spatially-dispersive lasers” , in Technical Digest of Optics in the Southeast , p. 154, Atlanta, USA (2005).
7. R. A. Sims, J. Kernal, V. V. Fedorov, S. B. Mirov, “Co:ZnS and Co:ZnSe saturable absorbers for alexandrite laser”, in Technical Digest of Optics in the Southeast , p. 65, Atlanta, USA (2005).
8. A.Gallian, V.V.Fedorov, L. Luke, I.S. Moskalev, S.B.Mirov, V.V. Badikov, “Cr2+:ZnSe Laser Pumped Utilizing Cr Ionization”, Technical Digest of Optics in the Southeast , p. 66, Atlanta, USA (2005).
9. R. A. Sims, J. Kernal, V. V. Fedorov, S. B. Mirov, “Characterization of cobalt doped ZnSe and ZnS crystals as saturable absorbers for alexandrite lasers”, Solid State Lasers XV: Technology And Devices , [6100-22] San Jose, California USA, 21–26 January (2006).
10. L. Luke, V. V. Fedorov, I. S. Moskalev, A. Gallian, S. B. Mirov, “Middle-infrared electroluminescence of n-type Cr doped ZnSe crystals”, Solid State Lasers XV: Technology And Devices , [6100-26] San Jose, California USA, 21–26 January , (2006).
11. Marquecho, R. and R. Pitt (2005). “Metal Associations with Stormwater Particulates,” 78th Annual Water Environment Federation Technical Exposition and Conference. Washington, D.C. Oct. 29 – Nov. 2, 2005.
12. Pitt, R. and A. Maestre. “Stormwater quality as described in the National Stormwater Quality Database.” 10th International Conference on Urban Drainage, Copenhagen, Denmark. August 21-26, 2005.
13. Clark, S.E., M.M. Lalor, R. Pitt, and R. Field. “Wet-weather pollution from commonly-used building materials.” 10th International Conference on Urban Drainage, Copenhagen, Denmark. August 21-26, 2005.
14. Clark, S.E., P. Johnson, R. Pitt, S. Gill, and M. Pratap. “Filtration for metals removal from stormwater.”10th International Conference on Urban Drainage, Copenhagen, Denmark. August 21-26, 2005.
15. Clark, S., M.M. Lalor, and R. Pitt. “Wet-weather pollution from commonly-used building materials.” World Water and Environmental Resources Congress. ASCE/EWRI. Anchorage, Alaska. May 2005.
16. Pratap, M., U. Khambhammettu, S. Clark, and R. Pitt. “Stormwater treatment using upflow filters.” World Water and Environmental Resources Congress. ASCE/EWRI. Anchorage, Alaska. May 2005.
17. Morquecho, R. and R. Pitt. “Chemical forms and effects of heavy metals in stormwater.” World Water and Environmental Resources Congress. ASCE/EWRI. Anchorage, Alaska. May 2005.
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Patents (2005-2006)
• US patent # 6,960,486 November 1, 2005• 2 US patent applications filed