an international journal for experimental and...

An international journal for experimental and theoretical physics

Best of 2011 articles collectionwww.physica.org

Reasons to publish with Physica ScriptaBy choosing to publish with Physica Scripta, you will benefit from:

• Straightforward publication process The publication process is 100% electronic — from submitting your article to receiving your proofs. Our standards of production quality are very high with full copy-editing and proof service for all articles.

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• Global readership In 2011, more than 244 000 Physica Scripta full-text articles were downloaded by readers from around the world. All articles are free to view online for 30 days from web publication, which helps to increase the visibility of your paper.

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Physica Scripta

w w w . p h y s i c a . o r g 3

Welcome to the Physica Scripta Best of 2011 articles collection

As Editor-in-Chief of Physica Scripta, I am pleased to present this compilation of journal highlights selected on the basis of downloads and citations to represent the most insightful, innovative and progressive work published in the journal during 2011.

The collection is intended to give readers a sample of the journal content and is not intended to be a definitive list of ‘best articles’. The full text for each article presented is freely available without subscription until the end of 2012.

Abstracts are ordered by PACS code, and have been chosen from each subject area to provide an overview of the broad scope covered in the journal. Several abstracts from Comments sections and from two Topical Issues published during 2011 have also been included.

Physica Scripta has shown a continuous growth in terms of submitted manuscripts, continuing throughout 2011, and the journal has become an important physics publication because of the high editorial standards. Editorial Board members are active researchers from top institutions, and all submitted papers are subject to rigorous peer review. Reviewers are encouraged to provide constructive feedback that can provide authors with assistance when improving their manuscripts. The final acceptance/rejection decision remains the responsibility of the Editors and currently about two out of three submissions to the journal are rejected. Summing up, the editors of Physica Scripta are active researchers within their topics and ensure expert constructive feedback is provided to the scientific community.

I hope that you enjoy the collection and find the articles of great interest as well as beneficial to your own work.

ImPact Factor

0.985**As listed in the 2010 ISI Journal

Citation Reports®

Fast Publication

25 daysAverage acceptance-to- online-publication time

Cover image: Spinning phenomena and energetics of spherically pulsating patterns in stratified fluids. Top: contour plots of the invariant solution for the stream function; middle: spinning phenomena; bottom: effects of nonlinearity on the spinning phenomenon (adapted from R N Ibragimov and M Dameron 2011 Phys. Scr. 84 015402; artistic impression by Frédérique Swist).

Prof. Roger WäpplingEditor-in-Chief, Physica Scripta

Physica ScriptaISSN 0031-8949


A journal of the Royal Swedish Academy of Sciences published by IOP Publishing

Featured in this issueComments on Astrophysics and Cosmology

PAPERS

GENERAL PHYSICS

045001 J-Matrix approach for the exponential-cosine-screened Coulomb potentialI Nasser, M S Abdelmonem and Afaf Abdel-Hady

045002 Universal quantum computing with nanowire double quantum dotsPeng Xue

045003 An analysis of the applications of the modified Kratzer potentialAli Akbar Babaei-Brojeny and Mojtaba Mokari

045004 On a (2+1)-dimensional Madelung system with logarithmic and with Bohm quantum potentials:Ermakov reductionColin Rogers and Hongli An

045005 On the photon distribution of the two-mode squeezed chaotic stateJun Zhou, Hong-yi Fan and Jun Song

045006 Entanglement swapping of a GHZ state via a GHZ-like stateChia-Wei Tsai and Tzonelih Hwang

045007 Synthetic multicellular oscillatory systems: controlling protein dynamics with genetic circuitsAneta Koseska, Evgenii Volkov and Jurgen Kurths

045008 Magnetic operations: a little fuzzy mechanics?B Mielnik and A Ramırez

045009 Optimization analysis of the performance of an irreversible Ericsson refrigeration cycle in themicro/nanoscaleHao Wang, Guoxing Wu and Yueming Fu

045010 Nonclassical properties of the integrability condition of the time-dependent SU(2) quantum systemM Sebawe Abdalla and E M Khalil

045011 Protecting the squeezing of a two-level system by detuning in non-Markovian environmentsXing Xiao, Mao-Fa Fang and Yan-Min Hu

045012 Combined effects of asymmetry and noise correlation on the noise-enhanced stability phenomenon in abistable systemDong-Cheng Mei, Zheng-Lin Jia and Can-Jun Wang

045013 Nonadditivity of quantum capacities of quantum multiple-access channels and the butterfly networkPeng Huang, Guangqiang He, Jun Zhu and Guihua Zeng

045014 Subquantum nonlocal correlations induced by the background random fieldAndrei Khrennikov

045015 Cryptanalysis of quantum secret sharing based on GHZ statesXiao-Fen Liu and Ri-Jing Pan

045016 Scalar field reconstruction of power-law entropy-corrected holographic dark energyEsmaeil Ebrahimi and Ahmad Sheykhi

045017 The chaotic atom model via a fractal approximation of motionM Agop, P Nica, S Gurlui, C Focsa, D Magop and Z Borsos

045018 Three-dimensional quantum key distribution in the presence of several eavesdroppersM Daoud and H Ez-zahraouy

(Continued on inside back cover)

Bibliographic codes CODEN: PHSTBO 84 (4) 045001–048401 (2011) ISSN: 0031-8949

Volume 84 Number 4 October 2011

Physica Scripta

Vol 84, No 4 045001–048401

October 2011


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PS84-4cover-UK.indd 2-4 12/10/2011 10:14

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Full-text downloads in 2011

244 185Published on behalf of the Physical Societies of the Nordic Countries by IOP Publishing and the Royal Swedish Academy of Sciences, Physica Scripta offers researchers a very flexible publishing service, making the journal an excellent choice for all theoretical and experimental physics.

Journal scopePhysica Scripta is an international journal for experimental and theoretical physics, comprising strong components of atomic, molecular and optical physics, plasma physics, condensed matter physics and mathematical physics.

The journal publishes Comments in six different sections and maintains a programme of Topical Issues alongside the regular 12 issues a year.

Physica Scripta celebrated its 40th anniversary in 2010 and continues to grow in strength, content, prestige and distribution.

Geographical distribution of full-text downloads

Geographical distribution of paper submissions

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Middle East6%

Asia32%

Australasia1%

North America6%


Africa9%

Western Europe6%UK

1% Eastern Europe7%

Middle East21%

Asia48%

Australasia0%

North America21%


Africa1%

Western Europe19%UK

4% Eastern Europe4%

Middle East6%

Asia32%

Australasia1%

North America6%


Africa9%

Western Europe6%UK

1% Eastern Europe7%

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Asia48%

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Publish your research in Physica ScriptaPhysica Scripta accepts a number of different types of papers.

CommentsComments describe the current thinking of leading researchers on outstanding problems. This may include discussion of open questions, questions that recent work has apparently closed, important new applications, new theoretical and experimental approaches, and predictions of future developments. Intended to bridge gaps in readers’ knowledge and provide insight into problems, methods and results in

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Each Comments section has its own designated Editor. Authors are encouraged to write articles of 2500–6000 words in length. Care should be taken to ensure that the article is accessible for non-experts and graduate students. Comments on controversial topics are desirable, provided that the author fairly represents all sides of the community.

Topical IssuesVolumes, published separately from the regular journal issues, contain invited presentations and/or poster contributions from international conferences highlighting cutting-edge research across key areas of physics.

Research papersReports of original research not normally more than 8500 words in length.

Managing EditorRoger Wäppling Uppsala University, Sweden

Comments EditorsComments on Atomic, Molecular and Optical Physics (CAMOP)H H Stroke New York University, USAH Linnartz Leiden Observatory, The Netherlands

Comments on Condensed Matter Physics (CCMP)L Dobrzynski Cardinal Stefan Wyszynski University and National Centre for Nuclear Research, Poland

Comments on Nuclear and Particle Physics (CNPP)U Heinz Ohio State University, Columbus, USAJ Räisänen University of Helsinki, Finland

Comments on Plasma Physics and Controlled Fusion (CPPCF)G Brodin Umeå University, SwedenJ Heikkinen VTT Processes, FinlandS Abarzhi University of Chicago, USA

Comments on Astrophysics and Cosmology (CAPC)B Gustafsson Uppsala University, Sweden Comments on Facilities and Research Projects (CFRP)L Thorlacius Science Institute, University of Iceland, Iceland

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about IoP Publishing

Physica Scripta is published by IOP Publishing on behalf of:

•The Royal Danish Academy of Sciences and Letters in cooperation with the Danish Physical Society•The Delegation of the Finnish Academies of Sciences and Letters in cooperation with the Finnish Physical Societies•The Icelandic Scientific Society in cooperation with the Icelandic Physical Society•The Norwegian Academy of Science and Letters in cooperation with the Norwegian Physical Society•The Royal Swedish Academy of Sciences in cooperation with the Swedish Physical Society

S Mannervik University of Stockholm, SwedenM Manninen University of Jyväskylä, FinlandH L Pécseli University of Oslo, Norway

D Röhrich University of Bergen, NorwayL Thorlacius Science Institute, University of Iceland, Iceland

L J Curtis University of Toledo, USAL Dobrzynski Cardinal Stefan Wyszynski University and National Centre for Nuclear Research, PolandJ Javanainen University of Connecticut, Storrs, USAM Man’ko Lebedev Physical Institute, RussiaS Mannervik University of Stockholm, SwedenK Mork Norwegian University of Science and Technology, Norway

R Nieminen Helsinki University of Technology, FinlandH L Pécseli University of Oslo, NorwayJ J Rasmussen Risø National Laboratory, DenmarkD Röhrich University of Bergen, NorwayL Stenflo Umeå University, SwedenM Y Yu Zhejiang University, China

Editorial Board

External Editors

Physica Scripta


Contents

Delay-improved signal propagation in globally coupled bistable systems 11J H Yang and X B Liu

Amplification of weak signals via the non-adiabatic regime of stochastic resonance in a bistable dynamical system 11 with time delay Lu-Chun Du and Dong-Cheng Mei

Electromagnetic potentials without gauge transformations 11A Chubykalo, A Espinoza and R Alvarado Flores

Coulomb screening of 2D massive Dirac fermions 11Jia-Ning Zhang

Resolution of the Klein paradox 12A D Alhaidari

On eigenvalue problems in quantum mechanics 12Aparna Saha, Umapada Das and B Talukdar

Accurate analytic approximation to the nonlinear pendulum problem 12M Turkyilmazoglu

The Schmidt number as a universal entanglement measure 12J Sperling and W Vogel

Characteristics of multiplicity distribution of target fragments in forward and backward hemispheres in high-energy 13 nucleus–nucleus interactions Dipak Ghosh, Argha Deb and Swarnapratim Bhattacharyya

Nuclear structure of the neutron-rich 140–148Ba isotopes 13A R H Subber and Falih H Al-Khudair

The mechanical, electronic structure and thermodynamic properties of B2-based AgRE studied from first-principles 13Xiaoma Tao, Hongmei Chen, Xingxiu Li, Yifang Ouyang and Shuzhi Liao

U-shaped multi-band negative-index bulk metamaterials with low loss at visible frequencies 14Kun Song, Quanhong Fu and Xiaopeng Zhao

Propagation of shock waves in a viscous medium 14Harish C Yadav and R K Anand

Optimization of the bubble radius in a moving single bubble sonoluminescence 14Mona Mirheydari, Rasoul Sadighi-Bonabi, Nastaran Rezaee and Homa Ebrahimi

General

Nuclear physics

Atomic and molecular physics

Electromagnetism, optics, acoustics, heat transfer, classical mechanics and fluid dynamics

)

Physica Scripta


Mixed convection boundary-layer flow about an isothermal solid sphere in a nanofluid 14L Tham, R Nazar and I Pop

Generation of continuous-variable entanglement in a three-level system coupled with a parametric oscillator 15Yong-Hong Ma

Power-flow formulation of a ray approach to the modelling of inhomogeneous waves 15M Tereshchenko, F Castejón, S Pavlov and A Cappa

Nonplanar ion-acoustic solitary waves in electron–positron–ion plasmas with electrons following a q-nonextensive distribution 15P Eslami, M Mottaghizadeh and Hamid Reza Pakzad

The 3+1 dimensional Kadomtsev–Petviashvili Burgers’ equation in non-uniform dusty plasmas 15Li-Ping Zhang, Ju-Kui Xue and Li-Hua Yuan

Experimental and theoretical studies of the direct-current breakdown voltage in argon at micrometer separations 16M Klas, Š Matejcík, B Radjenovic and M Radmilovic -Radjenovic

Electron acoustic solitary waves with kappa-distributed electrons 16S Devanandhan, S V Singh and G S Lakhina

Dust acoustic instability with Lorentzian kappa distribution 16Sanqiu Liu and Jing Li

Instabilities in strongly coupled ultracold neutral plasmas 16M Rosenberg and P K Shukla

Influence of gas pressure on the structure and dynamics of dust rotation in magnetized dusty plasmas 16F Huang, Y H Liu, M F Ye and L Wang

Electrical properties of the double perovskite oxide Ho2CuZrO6 17D K Mahato, Alo Dutta, Nishant Kumar and T P Sinha

The effect of heating conditions on the properties of nano- and microstructured Ni–Zn ferrite 17A Sutka, K A Gross, G Mezinskis, G Bebris and M Knite

Structural and dielectric properties of Cr-doped Ni–Zn nanoferrites 17S Nasir, M Anis-ur-Rehman and Muhammad Ali Malik

Structural, electrical and magnetic studies of nickel–zinc nanoferrites prepared by simplified sol–gel 18 and co-precipitation methods S Nasir and M Anis-ur-Rehman

Negative differential conductivity in bilayer graphene controlled by an external voltage and in the presence of a magnetic field 18N N Yanyushkina, M B Belonenko and N G Lebedev

Pseudopotential calculation of the bulk modulus and phonon dispersion of the bcc and hcp structures of titanium 18Mahmoud Jafari, Niloofar Zarifi, Maryam Nobakhti, Atefeh Jahandoost and Maryam Lame

Effect of substrate temperature in the synthesis of BN nanostructures 18M Sajjad, H X Zhang, X Y Peng and P X Feng

The fabrication, characterization and electrochemical corrosion behavior of Zn-TiO2 composite coatings 19M K Punith Kumar, T V Venkatesha, M K Pavithra and A Nithyananda Shetty

Physics of gases, plasmas and electrical discharges

Condensed matter: structural, mechanical and thermal properties

Physica Scripta


The structural, elastic and vibrational properties of the DyX (X=P, As) compounds 19H Özısık, Y Ö Çiftci, K Çolakoglu and E Deligöz

Physical and chemical properties of a Ga-doped ZnO crystal 19Arvids Stashans, Katia Olivos and Richard Rivera

A carbon nanotube-based pressure sensor 19Kh S Karimov, M Saleem, Z M Karieva, Adam Khan, T A Qasuria and A Mateen

Specific heat and magnetization studies of RMnO3 (R=Sm, Eu, Gd, Tb and Dy) multiferroics 20N Pavan Kumar, G Lalitha and P Venugopal Reddy

The photoluminescence and magnetism of nitrogen-implanted ZnO 20CM Liu, X Xiang, Y Zhang, HQ Gu, Y Jiang, M Chen and XT Zu

First-principles study of structural, elastic, electronic, lattice dynamic and optical properties of XN (X=Ga, Al and B) 20 compounds under pressure M Fatmi, B Ghebouli, M A Ghebouli and Z K Hieba

Electric field effects on the intersubband optical absorptions and refractive index in double-electron quantum dots 20Liangliang Lu and Wenfang Xie

Nonlinear transport through ultra-narrow zigzag graphene nanoribbons: non-equilibrium charge and bond currents 21Hosein Cheraghchi

Magnetic and transport properties of chemical solution deposited (100)-textured La0.7Sr0.3MnO3 and La0.7Ca0.3MnO3 21 nanocrystalline thin films Giray Kartopu, Orhan Yalçin and A Serdar Demiray

Improvement in the luminous efficiency of MEH-PPV based light emitting diodes using zinc oxide nanorods grown by the 21 electrochemical deposition technique on ITO substrates Rohini B Gupta, Jitender Kumar, Devinder Madhwal, Inderpreet Singh, I Kaur, L M Bhardwaj, S Nagpal, P K Bhatnagar and P C Mathur

Effect of pressure on the global and local properties of cubic perovskite crystals 22Tarik Ouahrani, I Merad-Boudia, H Baltache, R Khenata and Z Bentalha

Role of donor–acceptor domain formation and interface states in initial degradation of P3HT:PCBM-based solar cells 22Swati Arora, Satish Kumar Rajouria, Pankaj Kumar, P K Bhatnagar, Manoj Arora and R P Tandon

Synthesis and characterization of Cu doped cobalt oxide nanocrystals as methane gas sensors 22Z Sheikhi Mehrabadi, A Ahmadpour, N Shahtahmasebi and M M Bagheri Mohagheghi

Lorentz-covariant quantum transport and the origin of dark energy 23Arne Bergstrom

Ionospheric perturbations associated with two recent major earthquakes (M>5.0) 23S Priyadarshi, S Kumar and A K Singh

Cosmic microwave background radiation in an inhomogeneous spherical space 23R Aurich, P Kramer and S Lustig

Condensed matter: electronic structure, electrical, magnetic and optical properties

Interdisciplinary physics and related areas of science and technology

Geophysics, astronomy and astrophysics

)

Physica Scripta


Dimensions, nodes and phases in quantum numbers 23A R P Rau

Testing Lorentz symmetry with atoms and light 23Neil Russell

Optical tomography of Fock state superpositions 24S N Filippov and V I Man’ko

On multiple adsorptions of hydrogen atoms on graphene 24Benjamin J Irving, Anthony J H M Meijer and Dean Morgan

High-temperature superconductivity: the explanation 24A S Alexandrov

The pairing mechanism of high-temperature superconductivity: experimental constraints 24Guo-meng Zhao

Foundations of quantum mechanics? 25Göran Lindblad

Entanglement dynamics of two independent cavity-embedded quantum dots 25B Bellomo, G Compagno, R Lo Franco, A Ridolfo and S Savasta

Entanglement dynamics of a bipartite system in squeezed vacuum reservoirs 25Smail Bougouffa and Awatif Hindi

A smooth, holographically generated ring trap for the investigation of superfluidity in ultracold atoms 25Graham D Bruce, James Mayoh, Giuseppe Smirne, Lara Torralbo-Campo and Donatella Cassettari

Entanglement in two-mode continuous variable open quantum systems 26Aurelian Isar

An ECR ion source-based low-energy ion accelerator: development and performance 26A N Agnihotri, A H Kelkar, S Kasthurirangan, K V Thulasiram, C A Desai, W A Fernandez and L C Tribedi

At the borderline between atomic and nuclear physics: two-body β-decay of highly charged ions 26Yuri A Litvinov, Fritz Bosch, Christophor Kozhuharov, Xinwen Ma, Thomas Stöhlker, Nicolas Winckler and Takayuki Yamaguchi

Configuration and calibration of a flat field grating spectrometer in the wavelength range 7–60 Å with a Manson ultrasoft 26 x-ray source Y Yang, Z Shi, Z Fei, X Jin, J Xiao, R Hutton and Y Zou

Comments section (CAMOP)

Comments section (CCMP)

Comments section (CFRP)

Topical issue (T143)


Physica Scripta


Delay-improved signal propagation in globally coupled bistable systemsJ H Yang and X B Liu

Institute of Vibration Engineering Research, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, People’s Republic of China

E-mail: [email protected], [email protected]

2011 Phys. Scr. 83 065008

AbstractBased on the mechanism of vibrational resonance, we improve the weak low-frequency signal propagation in globally coupled bistable systems by time delay feedback. In the system chains, the weak low-frequency signal is added only to the first oscillator and the identical high-frequency signals are added to all of the oscillators. Both numerical and analytical results show that the response amplitude of the last oscillator to the low-frequency signal varies periodically with the delay parameter by two different periods, which equal the periods of the two exciting signals, respectively. In addition, the vibrational resonance can also be induced to improve signal propagation by adjusting the coupling strength. Comparing with the delay-free systems, with the cooperation of the high-frequency signal and time delay feedback, the weak low-frequency signal can be transmitted much more efficiently in the delayed systems.

Coulomb screening of 2D massive Dirac fermionsJia-Ning Zhang

Chern Institute of Mathematics, Nankai University, Tianjin 300071, People’s Republic of China

E-mail: [email protected]

2011 Phys. Scr. 83 035002

AbstractA model of 2D massive Dirac fermions, interacting with instantaneous 1/r Coulomb interaction, is presented in order to mimic the physics of gapped graphene. The static polarization function is calculated explicitly to analyze the screening effect at finite temperature and density. The results are compared with the massless case. We also show that various results in other works can be reproduced with our model in a straightforward and unified manner.

Amplification of weak signals via the non-adiabatic regime of stochastic resonance in a bistable dynamical system with time delayLu-Chun Du and Dong-Cheng Mei

Department of Physics, Yunnan University, Kunming 650091, People’s Republic of China


2011 Phys. Scr. 84 015003

AbstractThe non-adiabatic regime of stochastic resonance (SR) in a bistable system with time delay, an additive white noise and a periodic signal was investigated. The signal power amplification η was employed to characterize the SR of the system. The simulation results indicate that (i) in the case of intermediate frequency Ω of the periodic signal, the typical behavior of SR is lowered monotonically by increasing the delay time τ; in the case of large Ω, τ weakens the SR behavior and then enhances it, with a non-monotonic behavior as a function of time delay; (ii) time delay induces SR when A is above the threshold, whereas no such resonance exists in the absence of time delay; (iii) time delay induces a transition from bimodal to unimodal configuration of η; (iv) varying the particular form of time delay results in different phenomena.

Electromagnetic potentials without gauge transformationsA Chubykalo1, A Espinoza1 and R Alvarado Flores2

1 Unidad Academica de Fisica, Universidad Autonoma de Zacatecas, A.P. C-580, Zacatecas, Mexico

2 Centro de Estudios Multidisciplinarios, Universidad Autónoma de Zacatecas, Av. Insurgentes 108A, tercer piso, col. Centro, Zacatecas, Zac, C.p. 98000, Mexico


2011 Phys. Scr. 84 015009

AbstractIn this paper, we show that the use of the Helmholtz theorem enables the derivation of uniquely determined electromagnetic potentials without the necessity of using gauge transformation. We show that the electromagnetic field comprises two components, one of which is characterized by instantaneous action at a distance, whereas the other propagates in retarded form with the velocity of light. In our attempt to show the superiority of the new proposed method to the standard one, we argue that the action-at-a-distance components cannot be considered as a drawback of our method, because the recommended procedure for eliminating the action at a distance in the Coulomb gauge leads to theoretical subtleties that allow us to say that the needed gauge transformation is not guaranteed. One of the theoretical consequences of this new definition is that, in addition to the electric E and magnetic B fields, the electromagnetic potentials are real physical quantities. We show that this property of the electromagnetic potentials in quantum mechanics is also a property of the electromagnetic potentials in classical electrodynamics.

General

during 2011

27 300Monthly downloads as high as

Physica Scripta


Resolution of the Klein paradoxA D Alhaidari

Saudi Center for Theoretical Physics, Jeddah, Saudi Arabia


2011 Phys. Scr. 83 025001

AbstractWe present a resolution of the Klein paradox within the framework of one-particle relativistic quantum mechanics. Not only reflection becomes total but the vacuum remains neutral as well. This is accomplished by replacing the physical pair production process with virtual negative energy ‘incidence’ within the barrier in a similar manner to what is done with virtual sources in optics and image charges in electrostatics.

Accurate analytic approximation to the nonlinear pendulum problemM Turkyilmazoglu

Mathematics Department, University of Hacettepe, 06532 Beytepe, Ankara, Turkey


2011 Phys. Scr. 84 015005

AbstractThis paper is concerned with the accurate analytic solution of the nonlinear pendulum differential equation. Instead of the traditional Taylor series or asymptotic methods, the homotopy analysis technique is used, which does not require a small perturbation parameter or a large asymptotic parameter. It is shown here that such a method is extremely powerful in gaining the pendulum solution in terms of purely trigonometric cosine

The Schmidt number as a universal entanglement measureJ Sperling and W Vogel

Arbeitsgruppe Quantenoptik, Institut für Physik, Universität Rostock, D-18051 Rostock, Germany

E-mail: [email protected], [email protected], [email protected]

2011 Phys. Scr. 83 045002

AbstractThe class of local invertible operations is defined, and the invariance of entanglement under such operations is established. For the quantification of entanglement, universal entanglement measures are defined, which are invariant under local invertible transformations. They quantify entanglement in a very general sense. It is shown that the Schmidt number is a universal entanglement measure, which is most important for the general amount of entanglement. For special applications, pseudo-measures are defined to quantify the entanglement useful for a certain quantum task. The entanglement quantification is further specified by operational measures, which include the observables accessible by a given experimental setup.

On eigenvalue problems in quantum mechanicsAparna Saha1, Umapada Das2 and B Talukdar1

1 Department of Physics, Visva-Bharati University, Santiniketan 731235, India 2 Department of Physics, Abhedananda College, Sainthia 731234, India


2011 Phys. Scr. 83 065003

AbstractTo solve quantum mechanical eigenvalue problems using the algorithmic methods recently derived by Nikiforov and Uvarov (1988 Special Functions of Mathematical Physics (Basel: Birkhäuser)) and Ciftci et al (2003 J. Phys. A: Math. Gen. 36 11807), one needs to first convert the associated wave equation into hypergeometric or closely related forms. We point out that once such forms are obtained, the eigenvalue problem can be satisfactorily solved by only imposing the condition that the regular infinite series solutions of the equations should become polynomials, and one need not take recourse to the use of the algorithmic methods. We first demonstrate the directness and simplicity of our approach by dealing with a few case studies and then present new results for the Woods–Saxon potential.

functions. The obtained explicit analytical expressions for the frequency, period and displacement generate results that compare excellently with the numerically computed ones for moderate as well as sufficiently high values of the initial amplitudes. For larger initial amplitudes close to 180° Padé approximants of the found series solutions lead to fairly accurate results whose relative errors as compared with the exact values are less than 1%.

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Physica Scripta


Nuclear structure of the neutron-rich 140–148Ba isotopesA R H Subber and Falih H Al-Khudair

Department of Physics, College of Education, Basrah University, Basrah, Iraq


2011 Phys. Scr. 84 035201

AbstractThe level structure of even–even neutron-rich 140–148Ba isotopes was studied in the framework of the interacting boson model. The reduced transition probabilities B(E2) of these nuclei were calculated. A set of parameters was used in the calculation to approach the values with the measured data. It was pointed out that interacting boson approximations are equitably reliable for the description of spectra and other properties. It was found that there is a rapid transition between spherical and rotational shapes.

Characteristics of multiplicity distribution of target fragments in forward and backward hemispheres in high-energy nucleus–nucleus interactionsDipak Ghosh1, Argha Deb1 and Swarnapratim Bhattacharyya2,3

1 Department of Physics, Nuclear and Particle Physics Research Centre, Jadavpur University, Kolkata 700 032, India

2 Department of Physics, New Alipore College, L Block, New Alipore, Kolkata 700 053, India

3 Author to whom any correspondence should be addressed


2011 Phys. Scr. 84 015201

AbstractA detailed study on the mechanism of the evaporation of target fragments in the forward and backward hemispheres in 12C–AgBr interactions at 4.5A GeV, 28Si–AgBr interactions at 14.5A GeV, 16O–AgBr interactions at 60A GeV and 32S–AgBr interactions at 200A GeV is carried out in terms of the multiplicity distribution. The nature of the multiplicity distribution in the forward and backward hemispheres is found to be different across all the interactions. The asymmetry parameters and the forward–backward ratios were also calculated for the above-mentioned interactions. The asymmetry parameters and the forward–backward ratios from other nucleus–nucleus interaction data were compared with our results. The forward–backward ratios of target fragments are found to be nearly the same for all the nucleus–nucleus interactions. The forward–backward ratios of all the interactions are greater than 1, suggesting that the probability of emission of fragments in the forward hemisphere is higher than that in the backward direction. The multiplicity moment, entropy and reduced entropy, i.e. the ratio of entropy to average multiplicity of target fragments, are evaluated in both the forward and backward hemispheres for all the four above-mentioned interactions. The values of multiplicity moments are found to be energy independent up to 60A GeV energy in the backward hemisphere. The reduced entropy is also found to be almost energy independent to within experimental error in the backward hemisphere. No such observation can be made in the forward hemisphere. The total entropy of the target fragments is found to be higher in the forward hemisphere. A study of correlation in terms of the scaled variance was also carried out in both the hemispheres for all the nucleus–nucleus interactions. No systematic variation of correlation either with energy or with the size of the projectile nucleus has been noticed. The study yields quite interesting information on the mechanism of particle evaporation in the backward hemisphere.

Nuclear physics

The mechanical, electronic structure and thermodynamic properties of B2-based AgRE studied from first-principlesXiaoma Tao1, Hongmei Chen1, Xingxiu Li1, Yifang Ouyang1,2 and Shuzhi Liao2

1 Key Laboratory of New Processing Technology for Nonferrous Metals and Materials of the Ministry of Education, Department of Physics, Guangxi University, Nanning 530004, People’s Republic of China

2 Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of the Ministry of Education, Department of Physics, Hunan Normal University, Changsha 410081, People’s Republic of China


2011 Phys. Scr. 83 045301

AbstractThe lattice constants, formation enthalpies, bulk modulus, elastic constants and electronic structures of B2-based AgRE (RE=Sc, Y and La–Lu) have been calculated by means of first-principles based on the density functional theory. The shear modulus, Young’s modulus and Poisson’s ratio have been estimated from the calculated elastic constants. The electronic structures were calculated to give insight into the bonding mechanism in AgRE compounds. In addition, the Debye temperature, heat capacity, thermal expansion and Grüneisen parameter of AgRE compounds were obtained by applying the Debye model. The calculated lattice constants, formation enthalpies and elastic constants are all in good agreement with the available experimental data and other theoretical results. The formation enthalpy of B2-AgRE varies linearly with the density of states at the Fermi level.

Atomic and molecular physics

Physica Scripta


U-shaped multi-band negative-index bulk metamaterials with low loss at visible frequenciesKun Song, Quanhong Fu and Xiaopeng Zhao

Department of Applied Physics, Northwestern Polytechnical University, Xi’an 710129, People’s Republic of China


2011 Phys. Scr. 84 035402

AbstractWe study bulk negative-index metamaterials made up of U-shaped cells at visible frequencies that can realize multi-band negative refractive index with very low loss based on high-order resonance. The mechanism of multi-band negative refractive index can be interpreted by analyzing the transmission modes, current distribution, effective LC circuit models and kinetic energy of electrons. In the low-frequency region, the multi-band resonances are mainly due to the cell itself; in the high-frequency region, they are mainly due to the interaction between adjacent cells. Compared with cut-wire pairs, U-shaped cells can realize resonances more easily at high frequencies and produce more negative-index transmission bands.

Electromagnetism, optics, acoustics, heat transfer, classical mechanics and fluid dynamics

Propagation of shock waves in a viscous mediumHarish C Yadav and R K Anand

Department of Physics, University of Allahabad, Allahabad-211002, India


2011 Phys. Scr. 83 065402

AbstractA theoretical model for entropy production in a viscous medium due to the propagation of shock waves has been developed. An exact general solution is achieved for plane, cylindrical and spherical symmetries of shock waves in viscous flow, which on numerical substitutions gives variations in the entropy production, temperature ratio and particle velocity in the shock transition region with the coefficient of viscosity, specific heat ratio, shock strength, initial density and initial pressure.

Optimization of the bubble radius in a moving single bubble sonoluminescenceMona Mirheydari1,2, Rasoul Sadighi-Bonabi1, Nastaran Rezaee1,2 and Homa Ebrahimi1

1 Department of Physics, Sharif University of Technology, 11365-91, Tehran, Iran 2 Department of Physics, Islamic Azad University, Central Tehran Branch, 14676-86831, Tehran, Iran


2011 Phys. Scr. 83 055403

AbstractA complete study of the hydrodynamic force on a moving single bubble sonoluminescence in N-methylformamide is presented in this work. All forces exerted, trajectory, interior temperature and gas pressure are discussed. The maximum values of the calculated components of the hydrodynamic force for three different radii at the same driving pressure were compared, while the optimum bubble radius was determined. The maximum value of the buoyancy force appears at the start of bubble collapse, earlier than the other forces whose maximum values appear at the moment of bubble collapse. We verified that for radii larger than the optimum radius, the temperature peak value decreases.

Mixed convection boundary-layer flow about an isothermal solid sphere in a nanofluidL Tham1, R Nazar2 and I Pop3

1 Faculty of Agro Industry and Natural Resources, Universiti Malaysia Kelantan, Kelantan, Malaysia

2 School of Mathematical Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Selangor, Malaysia

3 Faculty of Mathematics, University of Cluj, Cluj, Romania


2011 Phys. Scr. 84 025403

AbstractThe steady mixed convection boundary-layer flow of a nanofluid about a solid sphere with constant surface temperature has been studied for cases of both assisting and opposing flows. The resulting system of nonlinear partial differential equations is solved numerically using an implicit finite-difference scheme known as the Keller-box method. The solutions for the flow and heat-transfer characteristics are evaluated numerically for various values of the parameters, namely the nanoparticle volume fraction { and the mixed convection parameter λ at Prandtl numbers Pr=0.7 and 6.2. The three different types of nanoparticles considered are Al

2O3, Cu and TiO2, using water-based fluid with Pr=6.2. It is found that for each particular nanoparticle, as the nanoparticle volume fraction { increases, the skin friction coefficient and the heat-transfer rate at the surface also increase. This leads to an increase in the value of the mixed convection parameter λ, which at first gives no separation.

Physica Scripta


Generation of continuous-variable entanglement in a three-level system coupled with a parametric oscillatorYong-Hong Ma

School of Mathematics, Physics and Biological Engineering, Inner Mongolia University of Science and Technology, Baotou 014010, People’s Republic of China


2011 Phys. Scr. 83 025403

AbstractWe consider a nondegenerate three-level cascade laser driven by a classical field with a parametric oscillator. The dynamic evolution of the master equation is investigated and the steady-state entanglement between two modes is investigated. We show that introducing the parametric oscillator can enhance the entanglement between the two-mode cavity. In particular, with the help of the classical field, a high intensity of entangled light between the two modes can be achieved.

Power-flow formulation of a ray approach to the modelling of inhomogeneous wavesM Tereshchenko1,4, F Castejón1,3, S Pavlov2 and A Cappa3

1 Instituto de Biocomputación y Física de Sistemas Complejos, 50018 Zaragoza, Spain

2 Institute of Plasma Physics, KhIPT, 61108 Kharkov, Ukraine 3 Laboratorio Nacional de Fusión, EURATOM-CIEMAT, 28040 Madrid, Spain 4 Prokhorov Institute of General Physics, 119991 Moscow, Russia


2011 Phys. Scr. 84 025401

AbstractIn this paper, we elaborate on quite a simple analytical framework for the physically intelligible principle of a ray description of inhomogeneous wavefields on the basis of the generic properties of active and reactive wave power flows. While being very close to traditional geometric optics (GO) in the limit of lossless media, in substantially non-Hermitian systems this approach turns out to be a distinct method capable of keeping up ray trajectories in a real-valued domain. We also demonstrate that the ray method based on power-flow analysis is mostly free from the standard limitations of GO. In this regard, the proper use of the ray-tracing technique can be justified for modelling a wide range of non-regular wave phenomena if wave power transport is under consideration. The paraxial equations are shown to comply with the power-flow formulation, thus finding an extended range of applicability.

Nonplanar ion-acoustic solitary waves in electron–positron–ion plasmas with electrons following a q-nonextensive distributionP Eslami1, M Mottaghizadeh2 and Hamid Reza Pakzad3,4

1 Department of Physics, Ferdowsi University, Mashhad, Iran 2 Department of Physics, Mashhad Branch, Islamic Azad University, Mashhad, Iran 3 Department of Physics, Bojnourd Branch, Islamic Azad University, Bojnourd, Iran 4 Author to whom any correspondence should be addressed


2011 Phys. Scr. 83 065502

AbstractCylindrical and spherical Korteweg–de Vries equations were derived for ion-acoustic solitary waves in an unmagnetized three species plasma system comprised of cold ions, nonextensive electrons and thermal positrons by using standard reductive perturbation methods. The effects of nonplanar geometry and q-nonextensive electrons on the profiles of the amplitudes and widths of solitary structures were examined numerically.

The 3+1 dimensional Kadomtsev–Petviashvili Burgers’ equation in non-uniform dusty plasmasLi-Ping Zhang1, Ju-Kui Xue2 and Li-Hua Yuan1

1 School of Sciences, LanZhou University of Technology, Lanzhou 730050, People’s Republic of China

2 College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070, People’s Republic of China


2011 Phys. Scr. 83 045501

AbstractUsing the perturbation method, the 3+1 dimensional modified variable coefficient Kadomtsev–Petviashvili (MKP) Burgers’ equation governing nonlinear dust acoustic shock waves is derived with the combined effects of non-adiabatic dust charge fluctuation, higher-order transverse perturbation and the non-thermally distributed ions in inhomogeneous dusty plasmas due to spatial gradients of dust charge and plasma densities for the first time. The MKP Burgers’ equation is reduced to the standard variable coefficient Kadomtsev–Petviashvili (KP) Burgers’ equation. A particular solution of this KP Burgers’ equation is also obtained. It is shown that the dust acoustic shock waves can exist in the KP Burgers’ equation.

Physics of gases, plasmas and electrical discharges

Physica Scripta


Influence of gas pressure on the structure and dynamics of dust rotation in magnetized dusty plasmasF Huang1, Y H Liu2, M F Ye2 and L Wang2

1 College of Science, China Agricultural University, Beijing 100083, People’s Republic of China

2 Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China


2011 Phys. Scr. 83 025502

AbstractThe structure and dynamics of dust rotation under a magnetic field at different gas pressures in the sheath of a radio-frequency discharge are

Experimental and theoretical studies of the direct-current breakdown voltage in argon at micrometer separationsM Klas1, Š Matejcík1, B Radjenovic2 and M Radmilovic-Radjenovic2

1 Department of Experimental Physics, Comenius University, Mlynská dolina F2, 84248 Bratislava, Slovakia

2 Institute of Physics, University of Belgrade, Pregrevica 118, 11080 Belgrade, Serbia


2011 Phys. Scr. 83 045503

AbstractIn this paper, the dc breakdown in argon has been measured in the discharge system consisting of two parallel planar Cu electrodes at separations from 20 to 500 μm varying the pressure from 4.5 to 690 torr. The measured breakdown voltage curves were systematically analyzed and a corresponding scaling law was suggested. The estimation of the secondary emission coefficient γ as a function of the reduced electric field was based on experimental data and simple theoretical studies. Additionally, particle-in-cell/Monte Carlo collision simulations were performed to understand in more detail the processes involved in the dc discharge breakdown. Good agreement was found between experimental and simulation results.

Electron acoustic solitary waves with kappa-distributed electronsS Devanandhan1, S V Singh1,2 and G S Lakhina1

1 Indian Institute of Geomagnetism, New Panvel (West), Navi Mumbai, India 2 School of Physics, University of Kwazulu-Natal, Durban, South Africa


2011 Phys. Scr. 84 025507

AbstractElectron acoustic solitary waves are studied in a three-component, unmagnetized plasma composed of hot electrons, fluid cold electrons and ions having finite temperatures. Hot electrons are assumed to have kappa distribution. The Sagdeev pseudo-potential technique is used to study the arbitrary amplitude electron-acoustic solitary waves. It is found that inclusion of cold electron temperature shrinks the existence regime of the solitons, and soliton electric field amplitude decreases with an increase in cold electron temperature. A decrease in spectral index, κ, i.e. an increase in the superthermal component of hot electrons, leads to a decrease in soliton electric field amplitude as well as the soliton velocity range. The soliton solutions do not exist beyond T

c/Th>0.13 for κ=3.0 and Mach number M=0.9 for the dayside auroral region parameters.

Dust acoustic instability with Lorentzian kappa distributionSanqiu Liu and Jing Li

Department of Physics, Nanchang University, Nanchang 330047, People’s Republic of China


2011 Phys. Scr. 84 035504

AbstractThe instability of dust acoustic waves (DAWs) driven by ions and electrons with different drift velocities in an unmagnetized, collisionless, isotropic dusty plasma was investigated based on kinetic theory. The electrons, ions and dust particles are all modeled by using the generalized Lorentzian kappa distributions. It is found that the instability growth rate depends not only on the mass, temperature, density ratios of the components and ion–electron drift velocity ratio, but also on the spectral index for each component. The effects of the indices on the instability growth rate of DAWs have been discussed in detail.

Instabilities in strongly coupled ultracold neutral plasmasM Rosenberg1 and P K Shukla2

1 Department of Electrical and Computer Engineering, University of California, San Diego, La Jolla, CA 92930, USA

2 RUB International Chair, International Centre for Advanced Studies in Physical Sciences, Faculty of Physics and Astronomy, Ruhr University Bochum, 44780 Bochum, Germany


2011 Phys. Scr. 83 015503

AbstractIn ultracold neutral plasmas the ions are strongly coupled in the liquid phase, while the electrons are weakly coupled. The effect of strong ion correlations on the dispersion relation of possible ion-beam plasma instabilities is considered.

Physica Scripta


Electrical properties of the double perovskite oxide Ho2CuZrO6D K Mahato1, Alo Dutta2, Nishant Kumar3 and T P Sinha2

1 Department of Physics, National Institute of Technology, Patna 800 005, India 2 Department of Physics, Bose Institute, 93/1, Acharya Prafulla Chandra Road, Kolkata 700 009, India

3 Department of Physics, T M Bhagalpur University, Bhagalpur 812007, India


2011 Phys. Scr. 84 015602

AbstractThe double perovskite oxide holmium copper zirconate, Ho2CuZrO6 (HCZ), was synthesized by a solid-state reaction technique. The crystal structure of HCZ shows a monoclinic phase. The dielectric relaxation of HCZ was investigated in the frequency range 44 Hz–1 MHz and in the temperature range 40–360 °C by using impedance spectroscopy. The complex impedance data were analysed by the Cole–Cole model. The ac conductivity follows the power law. The value of activation energy obtained from the temperature dependence of the dc conductivity plot indicates a hopping-type conduction mechanism. The scaling behaviour of the imaginary part of impedance indicates that relaxation in HCZ describes the same mechanism at various temperatures.

Condensed matter: structural, mechanical and thermal properties

The effect of heating conditions on the properties of nano- and microstructured Ni–Zn ferriteA Sutka1, K A Gross2, G Mezinskis1, G Bebris3 and M Knite4

1 Institute of Silicate Materials, Riga Technical University, Azenes 14/24, LV-1048, Latvia 2 Department of Materials Engineering, Monash University, VIC 3168, Australia 3 State Forensic Science Bureau, Hospitalu 55, LV-1013, Latvia 4 Institute of Technical Physics, Riga Technical University, Azenes 14/24, LV-1048, Latvia


2011 Phys. Scr. 83 025601

AbstractThe structural, microstructural and morphological, as well as electric and dielectric, properties of nickel–zinc ferrite (Ni0.3Zn0.7Fe2O4) derived from sol–gel auto-combustion have been studied after sintering from 900 to 1300 °C. The effect of heating rate has not been previously investigated and is reported here. X-ray diffraction showed a pure cubic spinel after calcination. Atomic force microscopy revealed nanosized particles after calcination, but scanning electron microscopy showed nanosized grains after sintering at 900 °C. The heating rate has a marked effect on oxidation of Fe3+ to Fe2+, showing an additional approach to control charge carrier concentration in Ni–Zn ferrites (powder and monoliths). The heating rate also influences the average particle size and distribution. Grain size and resistivity of sintered pellets do not show significant change with heating rate, proving that resistivity is mainly dictated by the number of grain boundaries. The dielectric loss tangent curves at room temperature exhibit dielectric relaxation peaks attributed to the similarity in frequency of charge hopping between the localized charge states and external fields. The relaxation peak shifts to higher frequencies for ferrites with nanosized grains.

Structural and dielectric properties of Cr-doped Ni–Zn nanoferritesS Nasir, M Anis-ur-Rehman and Muhammad Ali Malik

Applied Thermal Physics Laboratory, Department of Physics, COMSATS Institute of Information Technology, Islamabad 44000, Pakistan


2011 Phys. Scr. 83 025602

AbstractCr-doped Ni–Zn ferrite nanoparticles having the general formula Ni0.5Zn0.5CrxFe2−xO4 (x=0.1, 0.3, 0.5) were prepared by the simplified sol–gel method. The structural and dielectric properties of the samples sintered at 750±5 °C were studied. X-ray diffraction (XRD) patterns confirm the single-phase spinel structure of the prepared samples. The crystallite size calculated from the most intense peak (3 1 1) using the Debye–Scherrer formula was 29–34 nm. Scanning electron microscope images showed that the particle size of the samples lies in the nanometer regime. The dielectric constant (ε

r), dielectric loss tangent (tan δ) and ac electrical conductivity (σ

ac) of nanocrystalline Cr–Ni–Zn ferrites were investigated as a function of frequency and Cr concentration. The dependence of ε

r, tan δ and σac on the frequency of alternating applied electric field is in accordance with the Maxwell–Wagner model. The effect of Cr doping on the dielectric and electric properties was explained on the basis of cations distribution in the crystal structure.

investigated in this paper. The influence of gas pressure on the rotational properties of the dust particles located in different layers is studied in detail. Both rigid rotation (all the dust particles move with a constant angular velocity) and sheared rotation (the angular velocity of the dust particles has a radial distribution) of the dust particles induced by a magnetic field are observed. With increasing gas pressure, the angular velocity of the rotating dust particles in all layers decreases. Under specific experimental conditions, the angular velocity of the dust particles in the lower layer is lower than that of the dust particles in the upper layers. With increasing gas pressure, dust particles in the lower layer stop rotating earlier than those in the upper layers. At a critical (high) gas pressure, dust particles in the lower layers also reverse their rotation direction earlier than those in the upper layers. Within the same dust layer, particles located in the inner region stop rotating and reverse their rotation direction earlier than those in the outer region. At a sufficiently high angular velocity, a void (dust-free region) is formed in the dust cloud, leaving the dust particles rotating in a layer at the system edge. When the gas pressure becomes too high, the voids can be destroyed, and the dust particles are redistributed in the dust cloud. Finally, a 3D spindle-shaped configuration of the dust cloud in the plasma sheath can also be obtained. The experimental results are discussed in detail.

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Structural, electrical and magnetic studies of nickel–zinc nanoferrites prepared by simplified sol–gel and co-precipitation methodsS Nasir and M Anis-ur-Rehman

Applied Thermal Physics Laboratory, Department of Physics, COMSATS Institute of Information Technology, Islamabad 44000, Pakistan


2011 Phys. Scr. 84 025603

AbstractFerrite nanoparticles, particularly nickel–zinc ferrite nanoparticles, are novel materials for high-frequency applications. Nanoparticles with a composition of Ni

0.5Zn0.5Fe2O4 were prepared by two different processes, namely the co-precipitation and simplified sol–gel methods. Powder x-ray diffraction (XRD) patterns confirmed the single-phase spinel structure for the as-prepared samples. Samples were sintered at 555 and 755 °C, after which the structural, electrical and magnetic properties were studied. The crystallite sizes, as determined from XRD data, increased with sintering temperature. The dc electrical resistivity measurements were performed as a function of temperature, with the two-probe method in the temperature range from room temperature to 450 °C. The activation energy and drift mobility were calculated from the temperature-dependent dc electrical resistivity measurements. The dielectric constant and dielectric loss tangent for all the samples were determined as a function of frequency, and the frequency range used was from 20 Hz to 3 MHz at room temperature. The samples prepared using the simplified sol–gel method have lower dielectric constant values compared to those of the samples prepared using the co-precipitation method, and those prepared by the former method are more suitable for high-frequency applications. For the magnetic properties, a vibrating sample magnetometer was used. Saturation magnetization and coercivity increased with an increase in sintering temperature.

Negative differential conductivity in bilayer graphene controlled by an external voltage and in the presence of a magnetic fieldN N Yanyushkina1, M B Belonenko2 and N G Lebedev1

1 Volgograd State University, Volgograd, Russia 2 Volgograd Institute of Business, Laboratory of Nanotechnologies, Volgograd, Russia


2011 Phys. Scr. 83 015603

AbstractThe current–voltage characteristic of graphene bilayers was obtained in the case of strong electric and magnetic fields. Regions of negative differential conductivity were obtained when the magnetic field was perpendicular to the layers of the bilayer graphene. In addition, the possibility of generating terahertz pulses was discovered in such systems for a sufficiently wide range of interlayer voltage.

Pseudopotential calculation of the bulk modulus and phonon dispersion of the bcc and hcp structures of titaniumMahmoud Jafari1, Niloofar Zarifi1, Maryam Nobakhti1, Atefeh Jahandoost1 and Maryam Lame2

1 Physics Department, KN Toosi University of Technology, PO Box 16315-1618, Tehran, Iran

2 Shahid Rajaee University, Tehran, Iran


2011 Phys. Scr. 83 065603

AbstractThe structural stability of Ti in the hexagonal-closed-packed and body-centered cubic structures was studied by means of the full potential linearized augmented plane wave method. The effect of pressure on the bulk modulus of the crystal structures was investigated. In this study, the plane wave ultrasoft pseudopotential method was used to calculate the elastic constants, bulk modulus and phonon frequency of Ti. Phonon calculations were performed by employing the density functional perturbation theory in real space, using the calculated lattice dynamical force constants. All calculations were based on the density functional theory with the generalized gradient approximation and local density approximation, which well describe the properties of the above-mentioned metal.

Effect of substrate temperature in the synthesis of BN nanostructuresM Sajjad, H X Zhang, X Y Peng and P X Feng

Department of Physics, University of Puerto Rico, PO Box 23343, San Juan 00931, Puerto Rico


2011 Phys. Scr. 83 065601

AbstractBoron nitride (BN) nanostructures were grown on molybdenum discs at different substrate temperatures using the short-pulse laser plasma deposition technique. Large numbers of randomly oriented nanorods of fiber-like structures were obtained. The variation in the length and diameter of the nanorods as a function of the substrate temperature was systematically studied. The surface morphologies of the samples were studied using scanning electron microscopy. Energy dispersive x-ray spectroscopy confirmed that both the elements boron and nitrogen are dominant in the nanostructure. The x-ray diffraction (XRD) technique was used to analyse BN phases. The XRD peak that appeared at 26° showed the presence of hexagonal BN phase, whereas the peak at 44° was related to cubic BN content in the samples. Raman spectroscopic analysis showed vibrational modes of sp2- and sp3-type bonding in the sample. The Raman spectra agreed well with XRD results.

Physica Scripta


The structural, elastic and vibrational properties of the DyX (X=P, As) compoundsH Özısık1, Y Ö Çiftci2, K Çolakoglu2 and E Deligöz1

1 Department of Physics, Aksaray University, 68100 Aksaray, Turkey 2 Department of Physics, Gazi University, Teknikokullar, 06500 Ankara, Turkey


2011 Phys. Scr. 83 035601

AbstractA detailed theoretical study of the structural, elastic and vibrational properties of DyX (X=P, As) compounds is presented in this paper by performing ab initio calculations based on density functional theory using the VASP code. For describing the interaction between electrons and ions, the projector-augmented wave method is used. The generalized-gradient approximation is chosen for the exchange-correlation functional. The calculated structural parameters, such as the lattice constant, bulk modulus and second-order elastic constants, are presented. The high-pressure phase of both compounds is investigated and the phase transition pressure from NaCl (B1) to high-pressure phase (B2) is determined. To gain further information, we have calculated the Zener anisotropy factor (A), Poisson’s ratio (ν), Young’s modulus (E), shear modulus (C'), elastic wave velocities, Debye temperature, phonon frequencies and one-phonon density of states for the B1 structure of these compounds. The temperature-dependent variations of some thermodynamic properties such as entropy, heat capacity, internal energy and free energy are also predicted for the same compounds in the B1 phase.

The fabrication, characterization and electrochemical corrosion behavior of Zn-TiO2 composite coatingsM K Punith Kumar1, T V Venkatesha1, M K Pavithra1 and A Nithyananda Shetty2

1 Department of PG Studies and Research in Chemistry, Kuvempu University, Shankaraghatta 577 451, India

2 Department of Chemistry, National Institute of Technology Karnataka, Surathkal 575 025, India


2011 Phys. Scr. 84 035601

AbstractMetal-nanoparticle composite coatings improve the hardness, wear resistance and corrosion resistance properties of metal coatings. In this work, TiO

2 nanoparticles were chosen as second-phase particles to generate anticorrosive Zn composite coatings. The TiO

2 nanoparticles were dispersed in a Zn plating solution to co-deposit them with Zn. The Zn-TiO

2 composite coatings were then characterized by scanning electron microscopy (SEM), energy-dispersive x-ray spectroscopy (EDS) and x-ray diffraction methods. The presence of TiO

2 particles in the composite was confirmed by SEM images and EDS spectra. The Zn-TiO

2 composite coatings incorporated with different amounts of TiO

2 particles were tested for corrosion performance by polarization and electrochemical impedance spectroscopy, and the dissolution behavior of the coatings that had been immersed in corrosive media for a long time was studied. Improved corrosion resistance properties of the Zn-TiO

2 composite coatings were confirmed by polarization studies, fitted Nyquist plots, an increase in phase angle and a shift in the R

ct characteristic peak of the Bode plot.

Physical and chemical properties of a Ga-doped ZnO crystalArvids Stashans1, Katia Olivos1,2 and Richard Rivera1

1 Grupo de Fisicoquímica de Materiales, Universidad Técnica Particular de Loja, Apartado 11-01-608, Loja, Ecuador

2 Escuela de Geología y Minas, Universidad Técnica Particular de Loja, Apartado 11-01-608, Loja, Ecuador


2011 Phys. Scr. 83 065604

AbstractFirst-principles calculations based on density functional theory and strengthened by Hartree–Fock computations have been performed to study a Ga-doped wurtzite-type ZnO crystal. The large 108-atom supercell used throughout this work allows one to model a single point defect within the periodic supercell model. Thus, the Ga impurity produced purely local effects on the properties of the material. The electronic band structure was obtained for both pure and impurity-doped materials. The occurrence of free electrons in the conduction band was observed after the incorporation of Ga, implying the Ga dopant’s contribution to n-type electrical conductivity in the ZnO crystal, in agreement with known experimental data. An analysis of the charges on atoms and obtained atomic displacements in the region surrounding the defect showed that there is some alteration in the chemical bonding because of the presence of Ga atoms. In particular, the ionic bonding is strengthened in the defect’s neighbourhood.

A carbon nanotube-based pressure sensorKh S Karimov1,2, M Saleem1,3, Z M Karieva4, Adam Khan1, T A Qasuria1 and A Mateen1

1 GIK Institute of Engineering Sciences and Technology, Topi 23640, District Swabi, Pakistan

2 Physical Technical Institute of Academy of Sciences, Rudaki Avenue 33, Dushanbe 734025, Tajikistan

3 Government College Township, Lahore 54770, Pakistan 4 Tajik Technical University, Rajabov Street 10, Dushanbe 734000, Tajikistan


2011 Phys. Scr. 83 065703

AbstractIn this study, a carbon nanotube (CNT)-based Al/CNT/Al pressure sensor was designed, fabricated and investigated. The sensor was fabricated by depositing CNTs on an adhesive elastic polymer tape and placing this in an elastic casing. The diameter of multiwalled nanotubes varied between 10 and 30 nm. The nominal thickness of the CNT layers in the sensors was in the range ~300–430 μm. The inter-electrode distance (length) and the width of the surface-type sensors were in the ranges 4–6 and 3–4 mm, respectively. The dc resistance of the sensors decreased 3–4 times as the pressure was increased up to 17 kN m−2. The resistance–pressure relationships were simulated.

Condensed matter: electronic structure, electrical, magnetic and optical properties

Physica Scripta


Electric field effects on the intersubband optical absorptions and refractive index in double-electron quantum dotsLiangliang Lu and Wenfang Xie

Department of Physics, College of Physics and Electronic Engineering, Guangzhou University, Guangzhou 510006, People’s Republic of China


2011 Phys. Scr. 84 025703

AbstractThe linear and nonlinear optical properties such as optical absorption and refractive index change associated with intersubband transitions in a two-electron quantum dot (QD) in the presence of an external electric field have been investigated theoretically by using the perturbation method. The exchange force, which is a strictly quantum mechanical phenomenon, has also been considered. Numerical results on typical GaAs/AlGaAs materials show that an increase of the electric field decreases the oscillator strengths, the peak positions of absorption coefficients as well as the refractive index changes. Additionally, an increase of the confinement frequency (dot size) increases (decreases) the absorption coefficients but does not significantly affect the refractive index changes. It is also observed that the intensity of the illumination and the relaxation time have drastic effects on nonlinear optical properties. Finally, we note that the optical absorption coefficients and refractive index changes of two electrons are about five times higher than that of a one-electron QD.

Specific heat and magnetization studies of RMnO3 (R=Sm, Eu, Gd, Tb and Dy) multiferroicsN Pavan Kumar, G Lalitha and P Venugopal Reddy

Department of Physics, Osmania University, Hyderabad 500007, India


2011 Phys. Scr. 83 045701

AbstractA series of multiferroic materials with the compositional formula RMnO3 (where R=Sm, Eu, Gd, Tb and Dy) were prepared by the well-known citrate gel technique. After characterizing the samples structurally, a systematic investigation of specific heat and magnetization studies were performed over the temperature range 4–300 K with different magnetic fields. Based on these studies, it was found that all the samples exhibit a transition in the temperature region 39–54 K and the transition is attributed to ordering of Mn3+ ions (TN

Mn3+

). Further, the samples GdMnO3, TbMnO3 and DyMnO3 were found to exhibit another transition (T

lock) in the temperature range 20–29 K. Finally, yet another transition was exhibited by all the samples and it is attributed to the antiferromagnetic (AF) ordering of rare-earth ion moments (T

NR

3+

). The entropy at the AF transition TNMn

3+

was computed. Finally, using the specific heat data, the Debye temperature values were also calculated.

The photoluminescence and magnetism of nitrogen-implanted ZnOCM Liu1, X Xiang1, Y Zhang2, HQ Gu1, Y Jiang1, M Chen1 and XT Zu1

1 Department of Applied Physics, University of Electronic Science and Technology of China, Chengdu 610054, People’s Republic of China

2 School of Physics, Peking University, Beijing 100871, People’s Republic of China


2011 Phys. Scr. 83 045704

AbstractSingle crystal ZnO was implanted using nitrogen ions with an energy of 60 keV. The microstructure, photoluminescence (PL) and magnetism were studied in detail. Except for nitrogen, no other impurity can be detected by x-ray photoelectron spectra measurements. The room temperature PL of pure ZnO consists of a weak ultraviolet (UV) emission band and a strong green emission band. The PL and electrical conductivity can be suppressed by nitrogen implantation or by annealing in air. However, the two emission bands of pure ZnO can be enhanced intensively by Ar+ etching. The PL is related to the structure defects. Moreover, the intensity of UV luminescence is likely correlated to the electrical conductivity. Ferromagnetism cannot be obtained in the nitrogen-implanted sample from 77 to 300 K. The absence of ferromagnetism in nitrogen-implanted ZnO may be because there is no strong interaction between N 2p and O 2p electrons as nitrogen is a deep acceptor in ZnO.

First-principles study of structural, elastic, electronic, lattice dynamic and optical properties of XN (X=Ga, Al and B) compounds under pressureM Fatmi1, B Ghebouli2, M A Ghebouli3 and Z K Hieba4

1 Research Unit on Emerging Materials, University Ferhat Abbas of Setif, 19000, Algeria 2 Department of Physics, University Ferhat Abbas of Setif, 19000, Algeria 3 Department of Physics, Universitary Center of Bordj Bou-Arreridj, 34000, Algeria 4 Department of Physics, Faculty of Science, Taif University, Ta’if, Saudi Arabia


2011 Phys. Scr. 83 065702

AbstractWe have applied the pseudo-potential plane wave method to study the structural, elastic, electronic, lattice dynamic and optical properties of GaN and AlN in the wurtzite lattice and BN with zinc-blende structure. We have found that all elastic constants depend strongly on hydrostatic pressure, except for C

44 in wurtzite AlN and GaN that shows a weaker dependence. AlN and GaN present a direct band gap Γ–Γ, whereas BN has an indirect band gap Γ–X. The indirect Γ–K band gap in AlN occurs at about 35 GPa. The top of the valence bands reflects the p electronic character for all structures. There is a gap between optical and acoustic modes only for wurtzite phases AlN and GaN. All peaks in the imaginary part of the dielectric function for the wurtzite lattice GaN and AlN move towards lower energies, while those in the zinc-blende BN structure shift towards higher energies with increasing pressure. The decrease of the static dielectric constant and static refractive index in zinc-blende BN is weaker and it can be explained by its higher elastic constants.

Physica Scripta


Nonlinear transport through ultra-narrow zigzag graphene nanoribbons: non-equilibrium charge and bond currentsHosein Cheraghchi

School of Physics, Damghan University, PO Box 6715-364, Damghan, Iran


2011 Phys. Scr. 84 015702

AbstractThe electronic nonlinear transport through ultra-narrow graphene nanoribbons (sub-10 nm) was studied. A stable region of negative differential resistance (NDR) appears in the I–V characteristic curve of odd zigzag graphene nanoribbons (ZGNRs) at both positive and negative polarity. This NDR originates from a transport gap induced by a selection rule that blocks the electron transition between disconnected energy bands of ZGNR. Based on this transition rule, the on/off ratio of the current increases exponentially with ribbon length up to 105. In addition, charging effects and the spatial distribution of bond currents were studied by using the non-equilibrium Green’s function formalism in the presence of electron–electron interaction at a mean-field level. We also performed an ab initio density functional theory calculation of the transmission through a passivated graphene nanoribbon to demonstrate the robustness of the transport gap against hydrogen termination of the zigzag edges.

Improvement in the luminous efficiency of MEH-PPV based light emitting diodes using zinc oxide nanorods grown by the electrochemical deposition technique on ITO substratesRohini B Gupta1, Jitender Kumar1, Devinder Madhwal1, Inderpreet Singh1, I Kaur2, L M Bhardwaj2, S Nagpal1, P K Bhatnagar1 and P C Mathur1

1 Material Science Laboratory, Department of Electronic Science, University of Delhi South Campus, New Delhi, India

2 Central Scientific Instruments Organization, Sector-30, Chandigarh, India


2011 Phys. Scr. 84 015705

AbstractZinc oxide (ZnO) nanorods grown by the electrochemical technique have been used to enhance the luminance of poly[2-methoxy-5-(2’-ethylhexoxy)-1,4-phenylenevinylene] (MEH-PPV)-based polymer light-emitting diodes. The luminance of the device with ZnO nanorods is found to increase by more than two times as compared with the device without ZnO nanorods. The diameter of the nanorods used in device fabrication was ~145 nm. The size of the nanorods was estimated from field emission scanning electron microscope images. Optical and structural characterizations of the nanorods were also performed by using absorption, photoluminescence and x-ray diffraction, confirming the formation of ZnO nanorods.

Magnetic and transport properties of chemical solution deposited (100)-textured La0.7Sr0.3MnO3 and La0.7Ca0.3MnO3 nanocrystalline thin filmsGiray Kartopu1,2, Orhan Yalçin2 and A Serdar Demiray3

1 Institute for Materials and Surface Technology, University of Applied Sciences Kiel, Grenzstrasse 3, 24149 Kiel, Germany

2 Department of Physics, Faculty of Science, Nigde University, 51240 Nigde, Turkey 3 Department of Physics, Gebze Institute of Technology, 41400 Gebze, Kocaeli, Turkey


2011 Phys. Scr. 84 015702

AbstractA study of the magnetic and electrical properties of (100)-oriented La0.7(Sr,Ca)0.3MnO3 thin films prepared by an optimized chemical solution deposition process on a (100) SrTiO

3 single-crystal substrate is reported in this paper. The films were studied by high-resolution scanning electron microscopy, x-ray diffraction, vibrating sample magnetometer, ferromagnetic resonance and four-point-probe electrical measurements. A characteristic nanocrystalline texture with ~15 nm crystallites is observed in both films. Remarkably, the resistivities of these films are three orders of magnitude smaller compared with unoptimized films grown even on the same substrate. The magnetotransport properties were determined as a function of temperature and applied field magnitude, and compared with bulk crystals and vacuum-deposited single crystalline (epitaxial) thin films as well as manganite nanostructures reported in the literature. Both films display large values of colossal magnetoresistance at around room temperature. Significantly, the magnetoresistance in (100) La

0.7Sr0.3MnO3 thin film is

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observed to be highly linear even at low fields near the metal–insulator transition temperature. However, the dependence of these promising properties on the nanocrystal size remains to be explored.

Physica Scripta


Effect of pressure on the global and local properties of cubic perovskite crystalsTarik Ouahrani1, I Merad-Boudia1, H Baltache2, R Khenata2,3 and Z Bentalha1

1 Laboratoire de Physique Théorique, Département de Physique, École Préparatoire Sciences et Techniques, BP 230, 13000 Tlemcen, Algeria

2 Laboratoire de Physique Quantique et de Modélisation Mathématique (LPQ3M), Université de Mascara, 29000 Mascara, Algeria

3 Department of Physics and Astronomy, Faculty of Science, King Saud University, PO Box 2455, Riyadh 11451, Saudi Arabia


2011 Phys. Scr. 84 025704

AbstractThe influence of pressure on the structural, elastic, thermal and bonding properties of four perovskite-type oxides AMO3 is studied from the point of view of the quantum theory of atoms in molecules. Ab initio investigations are performed by means of the full-potential linear augmented plane-wave method as implemented in the wien2k code. The integrated basin charges resulting from the topological analysis of electronic density provide a partition of the bulk modulus and compressibility into atomic contributions. Special attention is paid to the nonlinear behaviour of the local bonding properties.

Role of donor–acceptor domain formation and interface states in initial degradation of P3HT:PCBM-based solar cellsSwati Arora1, Satish Kumar Rajouria1, Pankaj Kumar2, P K Bhatnagar3, Manoj Arora4 and R P Tandon5

1 Department of Physics, Zakir Husian College, University of Delhi, Delhi-110002, India

2 National Physical Laboratory, New Delhi, India 3 Department of Electronics Science, South Campus, University of Delhi, Delhi-110016, India

4 Department of Physics, Ramjas College, University of Delhi, Delhi-110007, India 5 Department of Physics and Astrophysics, University of Delhi, Delhi-110007, India


2011 Phys. Scr. 84 055702

AbstractThis work is devoted to identifying the degradation mechanism in various structures of a poly(3-hexylthiophene) (P3HT):6,6-phenyl C61-butyric acid methyl ester (PCBM)-based solar cell. We have tried to identify the dominant initial degradation mechanism on the basis of experimental studies carried out on different structures of an organic solar cell. It is known that many of these problems can be solved by means of the following: using proper electrodes and a suitable annealing temperature and duration, improving the morphology of the active film and maintaining a donor–acceptor phase-segregated ordered network as far as possible. The present studies have been carried out both in the dark and under illumination, and it is suggested that initial degradation plays a key role

Interdisciplinary physics and related areas of science and technology

in device performance. The dominant degradation mechanism is the growth of the donor–acceptor complex with time, which not only reduces the effective surface area but also hampers the charge separation. The little change in V

OC and the significant change in JSC suggest that once the LiF/Al electrode is improved, one must modify the structure either by introducing a thin layer of high-molecular-weight P3HT between PEDOT:PSS (poly(3,4-ethylenedioxythiopene) poly(styrenesulfonate)) and photoactive P3HT:PCBM layers or by introducing an optimized content of P3HT nanofibrils/nanoparticles into the P3HT:PCBM blend. The best structure was found to be ITO/PEDOT:PSS/P3HT:PCBM/LiF/Al and it can be improved by the above two methods.

Synthesis and characterization of Cu doped cobalt oxide nanocrystals as methane gas sensorsZ Sheikhi Mehrabadi1, A Ahmadpour1, N Shahtahmasebi2 and M M Bagheri Mohagheghi3

1 Nanotechnology Research Center, Department of Chemical Engineering, Ferdowsi University of Mashhad, Mashhad, Iran

2 Nanotechnology Research Center, Department of Physics, Ferdowsi University of Mashhad, Mashhad, Iran

3 School of Physics, Damghan University, Damghan, Iran


2011 Phys. Scr. 84 015801

AbstractIn this paper, nanoparticles of copper–cobalt compound oxide have been prepared by the sol–gel technique with different mole ratios of Cu/Co (ranging from 0.05 to 0.15) for the detection of methane gas, which is chemically a very stable hydrocarbon. The structural properties and morphology of the powders were studied by x-ray diffraction (XRD), Fourier transform infrared spectroscopy and transmission electron microscopy (TEM). By XRD analysis, we confirm that Co

3O4 and (CuO0.3CoO0.7) Co2O4 phases are formed and mean grain size is decreased with increasing Cu doping (from 28 to 24 nm). On the basis of TEM images, it is found that these particles possess a cubic structure with nearly uniform distribution. Also, gas-sensing measurements reveal that the optimal operating temperature is 300 °C, that the use of Cu as a dopant improved the sensing properties of cobalt oxide and that the sensitivity increased considerably with Cu concentration. The best sensitivity properties of nanosensors have been found at the mole ratios of Cu/Co of 0.125 and 0.15.

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25 daysDID YoU KNoW?

Physica Scripta


Lorentz-covariant quantum transport and the origin of dark energyArne Bergstrom

B&E Scientific Ltd, Seaford BN25 4PA, UK


2011 Phys. Scr. 83 045301

AbstractA possible explanation for the enigma of dark energy, responsible for about 76% of the mass–energy of the universe, is obtained by requiring only that the rigorous continuity equation (the Boltzmann transport equation) for quanta propagating through space should have the form of a Lorentz-covariant and dispersion-free wave equation. This requirement implies (i) properties of space–time that an observer would describe as uniform expansion in agreement with Hubble’s law and (ii) that the quantum transport behaves like in a multiplicative medium with multiplication factor ν=2. This inherent, essentially explosive multiplicity of vacuum, caused by the requirement of Lorentz covariance, is suggested as a potential origin of dark energy. In addition, it is shown (iii) that this requirement of Lorentz-covariant quantum transport leads to an apparent accelerated expansion of the universe.

Geophysics, astronomy and astrophysics

Ionospheric perturbations associated with two recent major earthquakes (M>5.0)S Priyadarshi, S Kumar and A K Singh

Atmospheric Research Laboratory, Department of Physics, Banaras Hindu University, Varanasi 221005, India


2011 Phys. Scr. 84 045901

AbstractIn this paper, dual-frequency GPS data recorded at Varanasi (geographic latitude 25°16' N, longitude 82°59' E) have been analyzed to study the ionospheric perturbations in total electron content (TEC) due to two recent major earthquakes (M>5.0) whose main shocks occurred on 25 February and 12 March 2010. A monthly median of the TEC and associated inter-quartile range, upper bound and lower bound are utilized as a reference to identify abnormal signals during these two earthquakes. The results show anomalous depletions in the TEC. These pre-earthquake ionospheric anomalies appear within 6 days prior to the earthquakes. We have also analyzed the ELF and VLF spectra observed from the DEMETER micro-satellite above the epicenter of the earthquake to support the ionospheric anomalies prior to the earthquakes. A possible mechanism responsible for the ionospheric anomalies due to earthquakes is also discussed.

Cosmic microwave background radiation in an inhomogeneous spherical spaceR Aurich1, P Kramer2 and S Lustig1

1 Institut für Theoretische Physik, Universität Ulm, Albert-Einstein-Allee 11, D-89069 Ulm, Germany

2 Institut für Theoretische Physik der Universität, Auf der Morgenstelle 14, D-74076 Tübingen, Germany


2011 Phys. Scr. 84 055901

AbstractWe analyse the cosmic microwave background (CMB) radiation in spherical three-spaces with nontrivial topology. The focus is on an inhomogeneous space which possesses observer-dependent CMB properties. The suppression of the CMB anisotropies on large angular scales is analysed with respect to the position of the CMB observer. The equivalence of a lens space to a Platonic cubic space is shown and used for the harmonic analysis. We give the transformation of the CMB multipole radiation amplitude as a function of the position of the observer. General sum rules are obtained in terms of the squares of the expansion coefficients for invariant polynomials on the three-sphere.

Comments section (CAMOP)

Dimensions, nodes and phases in quantum numbersA R P Rau

Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803, USA


2011 Phys. Scr. 83 018101

AbstractStudents of quantum mechanics encounter discrete quantum numbers in a somewhat incoherent and bewildering number of ways. For each physical system studied, quantum numbers seem to be introduced in their own specific way, some enumerating from 1 and others from 0, without a common uniting thread. This essay presents a point of view that builds on dimensions, boundary conditions and various inputs that, while known, are often not brought together to present a simple, consistent picture. At the same time, some surprisingly sophisticated connections are also made.

Testing Lorentz symmetry with atoms and lightNeil Russell

Physics Department, Northern Michigan University, Marquette, MI, USA


2011 Phys. Scr. 84 038101

AbstractThis article reports on the Fifth Meeting on CPT and Lorentz Symmetry, CPT ’10, held at the end of June 2010 in Bloomington, Indiana, USA. The focus is on recent tests of Lorentz symmetry using atomic and optical physics.

Physica Scripta


Optical tomography of Fock state superpositionsS N Filippov1,2 and V I Man’ko1,2

1 Moscow Institute of Physics and Technology, Moscow, Russia 2 P N Lebedev Physical Institute, Moscow, Russia


2011 Phys. Scr. 83 058101

AbstractWe consider optical tomography of photon Fock state superpositions (FSS) in connection with recent experimental achievements. The emphasis is put on the fact that it suffices to represent the measured tomogram as a main result of the experiment. We suggest a test for checking the correctness of experimental data. Explicit expressions for optical tomograms of FSS are given in terms of Hermite polynomials. Particular cases of vacuum and low-photon-number state superposition are considered and the influence of thermal noise on state purity is studied.

On multiple adsorptions of hydrogen atoms on grapheneBenjamin J Irving, Anthony J H M Meijer and Dean Morgan

Department of Chemistry, University of Sheffield, Sheffield S3 7HF, UK


2011 Phys. Scr. 84 028108

AbstractFirst-principles calculations using the Vienna Ab Initio Simulation Package (VASP) have been performed in order to scrutinize the hydrogen–graphene interaction. Emphasis has been placed on how surface relaxation and the prior chemisorption of one, two and three hydrogen atoms on graphene affect the adsorption properties of an encroaching gas phase hydrogen atom. Chemisorption at the para site was found to be barrierless, while it has been shown that a stable ortho adsorbate can form directly from the gas phase. Adsorption of the third and fourth H atoms was found in all cases to have a significant barrier. The resultant minimum energy structures show a reasonable agreement with scanning tunneling microscopy images obtained by Hornekær et al (2007 Chem. Phys. Lett. 446 237).

High-temperature superconductivity: the explanationA S Alexandrov

Department of Physics, Loughborough University, Loughborough LE11 3TU, UK


2011 Phys. Scr. 83 035201

AbstractSoon after the discovery of the first high-temperature superconductor by Georg Bednorz and Alex Müller in 1986, the late Sir Nevill Mott in answering

Comments section (CCMP)

his own question ‘Is there an explanation?’ (1987 Nature 327 185) expressed the view that the Bose–Einstein condensation (BEC) of small bipolarons, predicted by us in 1981, could be the one. Several authors then contemplated BEC of real-space tightly bound pairs, but with a purely electronic mechanism of pairing rather than with an electron–phonon interaction (EPI). However, a number of other researchers criticized the bipolaron (or any real-space pairing) scenario as incompatible with some angle-resolved photoemission spectra, with experimentally determined effective masses of carriers and unconventional symmetry of the superconducting order parameter in cuprates. Since then, the controversial issue of whether EPI is crucial for high-temperature superconductivity or is weak and inessential has been one of the most challenging problems of contemporary condensed matter physics. Here I outline some developments in the bipolaron theory suggesting that the true origin of high-temperature superconductivity is found in a proper combination of strong electron–electron correlations with a significant finite-range (Fröhlich) EPI, and that the theory is fully compatible with key experiments.

The pairing mechanism of high-temperature superconductivity: experimental constraintsGuo-meng Zhao1,2

1 Department of Physics, Faculty of Science, Ningbo University, Ningbo, People’s Republic of China

2 Department of Physics and Astronomy, California State University, Los Angeles, CA 90032, USA


2011 Phys. Scr. 83 038302

AbstractDeveloping a theory of high-temperature superconductivity in copper oxides is one of the outstanding problems in physics. It is a challenge that has defeated theoretical physicists for more than 20 years. Attempts to understand this problem are hindered by the subtle interplay among a few mechanisms and the presence of several nearly degenerate and competing phases in these systems. Here, we present some crucial experiments that place essential constraints on the pairing mechanism of high-temperature superconductivity. The observed unconventional oxygen-isotope effects in cuprates have clearly shown strong electron–phonon interactions and the existence of polarons and/or bipolarons. Angle-resolved photoemission and tunneling spectra have provided direct evidence for strong coupling to multiple-phonon modes. In contrast, these spectra do not show strong coupling features expected for magnetic resonance modes. Angle-resolved photoemission spectra and the oxygen-isotope effect on the antiferromagnetic exchange energy J in undoped parent compounds consistently show that the polaron binding energy is about 2 eV, which is over one order of magnitude larger than J = 0.14 eV. The normal-state spin-susceptibility data of hole-doped cuprates indicate that intersite bipolarons are the dominant charge carriers in the underdoped region, while the component of Fermi-liquid-like polarons is dominant in the overdoped region. All the experiments for testing the gap or order-parameter symmetry consistently demonstrate that the intrinsic gap (pairing) symmetry for the Fermi-liquid-like component is anisotropic s-wave and the order-parameter symmetry of the Bose–Einstein condensation of bipolarons is d-wave.

Physica Scripta


Comments section (CFRP)

Foundations of quantum mechanics?Göran Lindblad

Department of Theoretical Physics, Royal Institute of Technology, SE-106 91, Stockholm, Sweden


2011 Phys. Scr. 84 018501

AbstractDoes quantum mechanics have unsolved foundational problems? Is there a dividing line between the quantum and classical descriptions of the world? In this paper, I give an elementary introduction to the mathematical aspects of quantum and classical models which have prompted such questions.

Entanglement dynamics of two independent cavity-embedded quantum dotsB Bellomo1, G Compagno1, R Lo Franco1, A Ridolfo2 and S Savasta2

1 CNISM and Dipartimento di Scienze Fisiche ed Astronomiche, Università di Palermo, Via Archirafi 36, 90123 Palermo, Italy

2 Dipartimento di Fisica della Materia e Ingegneria Elettronica, Università di Messina, Via Salita Sperone 31, I-98166 Messina, Italy


2011 Phys. Scr. T143 014004

AbstractWe investigate the dynamical behavior of entanglement in a system made of two solid-state emitters, as two quantum dots, embedded in two separated microcavities. In these solid-state systems, in addition to the coupling with the cavity mode, the emitter is coupled to a continuum of leaky modes providing additional losses and is also subjected to a phonon-induced pure dephasing mechanism. We model this physical configuration as a multipartite system composed of two independent parts each containing a qubit embedded in a single-mode cavity, exposed to cavity losses, spontaneous emission and pure dephasing. We study the time evolution of entanglement of this multipartite open system, finally applying this theoretical framework to the case of currently available solid-state quantum dots in microcavities.


Entanglement dynamics of a bipartite system in squeezed vacuum reservoirsSmail Bougouffa1 and Awatif Hindi2

1 Department of Physics, Faculty of Science, Taibah University, PO Box 30002, Madinah, Saudi Arabia

2 Physics Department, College of Science, PO Box 22452, King Saud University, Riyadh 11495, Saudi Arabia


2011 Phys. Scr. T143 014006

AbstractEntanglement plays a crucial role in quantum information protocols; thus the dynamical behavior of entangled states is of great importance. In this paper, we suggest a useful scheme that permits a direct measure of entanglement in a two-qubit cavity system. It is realized through cavity-QED technology utilizing atoms as flying qubits. To quantify entanglement we use the concurrence. We derive the conditions that ensure that the state remains entangled in spite of the interaction with the reservoir. The phenomenon of entanglement sudden death in a bipartite system subjected to a squeezed vacuum reservoir is examined. We show that the sudden death time of the entangled states depends on the initial preparation of the entangled state and the parameters of the squeezed vacuum reservoir.

A smooth, holographically generated ring trap for the investigation of superfluidity in ultracold atomsGraham D Bruce, James Mayoh, Giuseppe Smirne, Lara Torralbo-Campo and Donatella Cassettari

Scottish Universities Physics Alliance, School of Physics and Astronomy, University of St Andrews, St Andrews, Fife KY16 9SS, UK


2011 Phys. Scr. T143 014008

AbstractWe discuss the suitability of holographically generated optical potentials for the investigation of superfluidity in ultracold atoms. By using a spatial light modulator and a feedback enabled algorithm, we generate a smooth ring with variable bright regions that can be dynamically rotated to stir ultracold atoms and induce superflow. We also comment on its future integration into a cold atom experiment.

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Physica Scripta


Entanglement in two-mode continuous variable open quantum systemsAurelian Isar

National Institute of Physics and Nuclear Engineering, PO Box MG-6, Bucharest-Magurele, Romania


2011 Phys. Scr. T143 014012

AbstractIn the framework of the theory of open systems based on completely positive quantum dynamical semigroups, we present a description of continuous-variable entanglement for a system consisting of two non-interacting modes embedded in a thermal environment. By using the Peres–Simon necessary and sufficient criterion for the separability of two-mode Gaussian states, we describe the evolution of entanglement in terms of the covariance matrix for Gaussian input states. For all values of the temperature of the thermal reservoir, an initial separable Gaussian state remains separable for all times. In the case of an entangled initial Gaussian state, entanglement suppression (entanglement sudden death) takes place for non-zero temperatures of the environment. Only for zero temperature of the thermal bath, the initial entangled state remains entangled for finite times. We also show that, independent of its type, namely separable or entangled, the initial state evolves asymptotically to an equilibrium state that is always separable.

An ECR ion source-based low-energy ion accelerator: development and performanceA N Agnihotri1, A H Kelkar1,3, S Kasthurirangan1,2, K V Thulasiram1, C A Desai1, W A Fernandez1 and L C Tribedi1

1 Tata Institute of Fundamental Research, Mumbai 400005, India 2 Institute of Chemical Technology, Matunga, Mumbai 400019, India 3 Present address: MPIKP, Heidelberg, Germany


2011 Phys. Scr. T144 014038

AbstractElectron cyclotron resonance (ECR) ion sources produce low-energy, highly charged ions. A new 14.5 GHz ECR-based low-energy ion accelerator facility has been developed. The ion source involves a plasma chamber (‘supernanogan’) surrounded by permanent magnets that provide a suitable magnetic field. The entire assembly including the ion source and the analyzing magnet is mounted on a 400 kV deck. A LabVIEW-based command and control system has been developed for the beamline. In addition, wireless communication has been installed to operate the machine in high voltage. The charge state distribution of several ions (He, N

2, O2, Ne, Ar and Xe) has been measured. For Ar and Xe, the maximum charge states measured were 16+ and 29+, respectively. A direct x-ray measurement for plasma diagnostics was also initiated.


At the borderline between atomic and nuclear physics: two-body β-decay of highly charged ionsYuri A Litvinov1,2, Fritz Bosch2, Christophor Kozhuharov2, Xinwen Ma3, Thomas Stöhlker2,4, Nicolas Winckler1 and Takayuki Yamaguchi5

1 Max-Planck Institut für Kernphysik, 69117 Heidelberg, Germany 2 GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany 3 Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, People’s Republic of China

4 Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, 69120 Heidelberg, Germany

5 Saitama University, 338-8570 Saitama, Japan


2011 Phys. Scr. T144 014001

AbstractIn this paper, we discuss the radioactive decay of highly charged ions. There are several motivations for performing this kind of research. One of them is that stellar nucleosynthesis proceeds at high temperatures and therefore the involved atoms are highly ionized. Highly charged ions also offer the possibility of addressing the decay of well-defined quantum-mechanical systems such as, for example, one-electron ions, where all the interactions with other electrons are excluded. These studies can be performed solely at ion storage rings or ion traps, where the high atomic charge states can be preserved for extended periods of time. Although we have focused on experiments conducted at the storage ring ESR of GSI, we have tried to describe the general requirements for such experiments.

Configuration and calibration of a flat field grating spectrometer in the wavelength range 7–60 Å with a Manson ultrasoft x-ray sourceY Yang, Z Shi, Z Fei, X Jin, J Xiao, R Hutton and Y Zou

The Key Laboratory of Applied Ion Beam Physics, Ministry of Education, People’s Republic of China

Shanghai EBIT Laboratory, Institute of Modern Physics, Fudan University, Shanghai, People’s Republic of China


2011 Phys. Scr. T144 014064

AbstractAn ultrasoft x-ray and extreme ultraviolet spectrometer built and calibrated in the wavelength range of 7–60 Å is reported here. Details of the alignment of this flat field spectrometer with both a laser and a telescope are presented. The light path function rather than a standard calibration function, i.e. a polynomial function, is introduced as the fit function, which gives good agreement with the spectrometer design values and makes the calibration more reliable when extended to the region outside the points used for calibration, compared with a standard calibration function. The calibration results of a Manson ultrasoft x-ray source (model 2) with source targets of Cu, Fe and Ti are presented with all the peaks marked.

Cover gallery




PAPERS

GENERAL PHYSICS

015001 Phantom-like effects in an asymmetric brane embedding with induced gravity and the Gauss–Bonnetterm in the bulkKourosh Nozari and Tahereh Azizi

015002 Multiple soliton solutions for a new coupled Ramani equationAbdul-Majid Wazwaz

015003 Coupled anharmonic oscillators: the Rayleigh–Ritz approach versus the collocation approachArkadiusz Kuros and Anna Okopinska

015004 Simulation of time delay effects in the intracellular calcium oscillation of cellsWei-Long Duan, Lin-Jing Yang and Dong-Cheng Mei

015005 Quantum capacity of Pauli channels with memoryPeng Huang, Guangqiang He, Yuan Lu and Guihua Zeng

015006 Solution of the Duffing–van der Pol oscillator equation by a differential transform methodSupriya Mukherjee, Banamali Roy and Sourav Dutta

015007 Localization of a wave function with channels of a quartic oscillator x2y2/2Jiann-Yeu Chen, Shao-Hua Chen and Tai-Chung Cheng

015008 Robust passivity analysis for Takagi–Sugeno fuzzy stochastic Cohen–Grossberg interval neural networkswith time-varying delaysG Nagamani and P Balasubramaniam

015009 Supersymmetric study of the pseudospin symmetry limit of the Dirac equation for a pseudoharmonicpotentialS Zarrinkamar, A A Rajabi and H Hassanabadi

015010 On the bound-state solutions of the Manning–Rosen potential including an improved approximation tothe orbital centrifugal termSameer M Ikhdair

015011 An improved numerical method for a class of astrophysics problems based on radial basis functionsK Parand, S Abbasbandy, S Kazem and A R Rezaei

015012 A new fifth-order nonlinear integrable equation: multiple soliton solutionsAbdul-Majid Wazwaz

015013 Non-Markovian dynamics of a three-level Λ-atom coupled to a structured reservoir: comparisonbetween the weak and strong coupling regimesXing Xiao, Mao-Fa Fang and Yan-Ling Li

015014 Energy of the Bardeen model using an approximate symmetry methodM Sharif and Saira Waheed

015015 On the behavior of high-order compact approximations in the one-dimensional sine–Gordon equationA Golbabai and M M Arabshahi

015016 The Luttinger liquid in superlattice structures: atomic gases, quantum dots and the classical Ising chainAranya B Bhattacherjee, Pradip Jha, Tarun Kumar and Man Mohan

015017 Lie point symmetries and similarity solutions for an electrically conducting Jeffrey fluidK S Mekheimer, S Z-A Husseny, A T Ali and R E Abo-Elkhair



Volume 83 Number 1 January 2011

Physica Scripta

Vol 83, No 1 015001–018101

January 2011

Volume 83 Number 1 January 2011

www.physica.org

PS83-1cover-UK.indd 2-4 06/01/2011 09:43



PAPERS

GENERAL PHYSICS

055001 Asymptotic iteration study of a two-electron GaAs quantum dotT Barakat and A S Al-Rawaf

055002 Energy in the spacetime field of the charged rotating BTZ black hole via approximate Lie symmetriesIbrar Hussain

055003 Entanglement of two superconducting charge qubits with the Glauber–Lachs stateHunkar Kayhan

055004 Hellmann potential in the J-matrix approach: I. EigenvaluesI Nasser and M S Abdelmonem

055005 Lie point symmetries and the time-independent integral of the damped harmonic oscillatorA Bhuvaneswari, R A Kraenkel and M Senthilvelan

055006 On the second law of thermodynamics in modified Gauss–Bonnet gravityH Mohseni Sadjadi

055007 Directed transport driven by correlated two-state noisesXiao-qun Huang, Xiao-miao Zhang, Zhi-e Ou and Bao-quan Ai

ATOMIC AND MOLECULAR PHYSICS

055301 Fine-structure energy levels, oscillator strengths and lifetimes in Cu XVIG P Gupta and A Z Msezane

ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS ANDFLUID DYNAMICS

055401 Magnetohydrodynamic Ekman layers with field-aligned flowManuel Nunez

055402 Experimental control of power dropouts by current modulation in a semiconductor laser with opticalfeedbackCatalin M Ticos, Ionut R Andrei, Mihail L Pascu and Mircea Bulinski

055403 Optimization of the bubble radius in a moving single bubble sonoluminescenceMona Mirheydari, Rasoul Sadighi-Bonabi, Nastaran Rezaee and Homa Ebrahimi

055404 Thomson scattering in the high intensity regimeMadalina Boca and Andreea Oprea

055405 Modification and control of the spontaneous emission from an M-type atom embedded in an anisotropicphotonic crystalChunling Ding, Jiahua Li, Xiaoxue Yang and Xin-You Lu

055406 Continuity equations for bound electromagnetic field and the electromagnetic energy–momentum tensorA L Kholmetskii, O V Missevitch and T Yarman

PHYSICS OF GASES, PLASMAS AND ELECTRIC DISCHARGES

055501 Effect of limiter biasing on runaway electrons in tokamaksM R Ghanbari, M Ghoranneviss, A Salar Elahi, M Tajdidzadeh and S Mohamadi

055502 Simplified models for the nonlinear evolution of two fast-particle-driven modes near the linear stabilitythresholdGrzegorz Galant, Jarosław Zalesny, Mietek Lisak, PawełBerczynski and Stefan Berczynski



Volume 83 Number 5 May 2011

Physica Scripta

Vol 83, No 5 055001–058101

May 2011

Volume 83 Number 5 May 2011A journal of the Royal Swedish Academy of Sciences published by IOP Publishing

Featured in this issueComments on Atomic, Molecular and Optical Physics

www.physica.org

PS83-5cover-UK.indd 2-4 05/05/2011 13:52





PAPERS

GENERAL PHYSICS

035001 Multiple-kink solutions for the (3+1)-dimensional Burgers hierarchyAbdul-Majid Wazwaz

035002 Analysis of non-paraxial solitons using a collective variable approachSerge I Fewo, Hermance Moussambi and Timoleon C Kofane

035003 N-soliton solution and soliton collisions of the (2+1)-dimensional nonlinear long-wave Boussinesq-classequationKun Sun, Bo Tian, Wen-Jun Liu, Min Li, Pan Wang and Yan Jiang

035004 Frozen time in hyperbolic spacetime motionArne Bergstrom

035005 New special structures to the (2+1)-dimensional breaking soliton equationsHuiqun Li, Xiaomin Wan, Zuntao Fu and Shikuo Liu

035006 Infinite-time and finite-time synchronization of coupled harmonic oscillatorsS Cheng, J C Ji and J Zhou

035007 On the quantum information entropies and squeezing associated with the eigenstates of the isotonicoscillatorA Ghasemi, M R Hooshmandasl and M K Tavassoly

035008 Underlining some limitations of the statistical formalism in quantum mechanicsF Fratini and A G Hayrapetyan

035009 Non-equilibrium phase transition in the kinetic Ising model driven by a propagating magnetic field waveMuktish Acharyya

035010 A new (2 + 1)-dimensional Korteweg–de Vries equation and its extension to a new (3 + 1)-dimensionalKadomtsev–Petviashvili equationAbdul-Majid Wazwaz

035011 Semiclassical charge transfer in gravitational encountersS F C Shearer, C J McGrath and D S F Crothers

NUCLEAR PHYSICS

035201 Nuclear structure of the neutron-rich 140−148Ba isotopesA R H Subber and Falih H Al-Khudair

035202 J/ψ production and the elliptic flow parameter v2 at LHC energyR Peng and C B Yang


035401 Coherent spectroscopy of a Λ atomic system and its prospective application to tunable frequency offsetlockingY B Kale, Ayan Ray, Q V Lawande and B N Jagatap

035402 U-shaped multi-band negative-index bulk metamaterials with low loss at visible frequenciesKun Song, Quanhong Fu and Xiaopeng Zhao



Volume 84 Number 3 September 2011

Physica Scripta

Vol 84, No 3 035001–038101

September 2011

Volume 84 Number 3 September 2011

www.physica.org

PS84-3cover-UK.indd 2-4 05/09/2011 11:31




PAPERS

GENERAL PHYSICS

025001 Resolution of the Klein paradoxA D Alhaidari

025002 Quantization rule solution to the Hulthen potential in arbitrary dimension with a new approximatescheme for the centrifugal termSameer M Ikhdair and Jamal Abu-Hasna

025003 Fault-tolerant quantum secret sharing against collective noiseYu-Guang Yang, Yi-Wei Teng, Hai-Ping Chai and Qiao-Yan Wen

025004 Entanglement concentration using a path–spin hybrid-entangled stateLiu-Yong Cheng, Xiao-Qiang Shao and Shou Zhang

025005 The construction, properties and applications of a new bipartite coherent-entangled state in thetwo-mode Fock spaceXiang-Guo Meng, Ji-Suo Wang and Bao-Long Liang

025006 Synchronization of chaos in two mesoscopic shunted resistive–capacitive–inductive Josephson junctionsby means of a nonlinear van der Pol oscillatorSameer Al-Khawaja

025007 Nonclassical properties and generation of excited entangled coherent states of motion of a trapped ionZhongjie Wang

025008 Multiplicative noise-induced vibrational resonance in a monostable system with one high-frequency andtwo low-frequency forcesFeng Guo

025009 Stability of embedded solitons in higher-order NLS equationsDebabrata Pal, Sk Golam Ali and B Talukdar

THE PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

025101 Scattering of a focused Gaussian beam by an axisymmetric particle with a nonconcentric spherical coreE E M Khaled and M E M Aly


025301 Forbidden transitions in excitation by electron impact in Co3+: an R-matrix approachV Stancalie

025302 Relativistic configuration interaction calculations on Kα x-ray satellites of kryptonLi Zhang, Gang Jiang, Lianghuan Hao and Banglin Deng

025303 Multiple backscattering on monoelemental materials and albedo factors of 279, 320, 511 and 662 keVgamma photonsArvind D Sabharwal, B S Sandhu and Bhajan Singh

025304 Studies on the full vibrational energies and dissociation limits of some electronic states of Kr+2 and Xe+

2diatomic molecular ionsQunchao Fan, Weiguo Sun, Huidong Li and Hao Feng



Volume 83 Number 2 February 2011

Physica Scripta

Vol 83, No 2 025001–025902

February 2011

Volume 83 Number 2 February 2011

www.physica.org

PS83-2cover-UK.indd 2-4 04/02/2011 12:50




www.physica.org

PAPERS

GENERAL PHYSICS

065001 Exact spatiotemporal wave and soliton solutions to the generalized (3+1)-dimensional nonlinearSchrodinger equation with linear potentialNikola Z Petrovic, Hussein Zahreddine and Milivoj R Belic

065002 Communication via an entangled coherent quantum networkA El Allati, Y Hassouni and N Metwally

065003 On eigenvalue problems in quantum mechanicsAparna Saha, Umapada Das and B Talukdar

065004 Robust state estimation for uncertain stochastic bidirectional associative memory networks withtime-varying delaysHaibo Bao and Jinde Cao

065005 Gap and out-gap solitons in modulated systems of finite length: exact solutions in the slowly varyingenvelope limitM Johansson, K Kirr, A S Kovalev and L Kroon

065006 Anti-synchronization between different chaotic complex systemsPing Liu and Shutang Liu

065007 Self-adjoint extensions and spectral analysis in the generalized Kratzer problemM C Baldiotti, D M Gitman, I V Tyutin and B L Voronov

065008 Delay-improved signal propagation in globally coupled bistable systemsJ H Yang and X B Liu

065009 Harmonic response of a class of finite extensibility nonlinear oscillatorsM Febbo

065010 Sinc and solitary wave solutions to the generalized Benjamin–Bona–Mahony–Burgers equationsMarwan Alqruan and Kamel Al-Khaled

065011 Synchronization of modified Colpitts oscillators with structural perturbationsSoup Tewa Kammogne and H B Fotsin


065301 Elastic scattering of positrons from hydrogen atoms with exponential cosine-screened Coulomb potentialsArijit Ghoshal and Y K Ho

065302 Quasirelativistic treatment of spectral characteristics of W37+

P Bogdanovich, O Rancova and A Stikonas


065401 The existence and stability of incoherently coupled bright–dark soliton families in photorefractivepolymersQichang Jiang, Yanli Su, Xuanmang Ji and Jinlai Wang

065402 Propagation of shock waves in a viscous mediumHarish C Yadav and R K Anand

065403 Hydrodynamic view of electrodynamics: energy rays and electromagnetic effective stressChia-Chun Chou and Robert E Wyatt



Volume 83 Number 6 June 2011

Physica Scripta

Vol 83, No 6 065001–069802

June 2011

Volume 83 Number 6 June 2011

PS83-6cover-UK.indd 2-4 01/06/2011 14:58




Featured in this issueComments on Astrophysics and Cosmology

PAPERS

GENERAL PHYSICS

045001 J-Matrix approach for the exponential-cosine-screened Coulomb potentialI Nasser, M S Abdelmonem and Afaf Abdel-Hady

045002 Universal quantum computing with nanowire double quantum dotsPeng Xue

045003 An analysis of the applications of the modified Kratzer potentialAli Akbar Babaei-Brojeny and Mojtaba Mokari

045004 On a (2+1)-dimensional Madelung system with logarithmic and with Bohm quantum potentials:Ermakov reductionColin Rogers and Hongli An

045005 On the photon distribution of the two-mode squeezed chaotic stateJun Zhou, Hong-yi Fan and Jun Song

045006 Entanglement swapping of a GHZ state via a GHZ-like stateChia-Wei Tsai and Tzonelih Hwang

045007 Synthetic multicellular oscillatory systems: controlling protein dynamics with genetic circuitsAneta Koseska, Evgenii Volkov and Jurgen Kurths

045008 Magnetic operations: a little fuzzy mechanics?B Mielnik and A Ramırez

045009 Optimization analysis of the performance of an irreversible Ericsson refrigeration cycle in themicro/nanoscaleHao Wang, Guoxing Wu and Yueming Fu

045010 Nonclassical properties of the integrability condition of the time-dependent SU(2) quantum systemM Sebawe Abdalla and E M Khalil

045011 Protecting the squeezing of a two-level system by detuning in non-Markovian environmentsXing Xiao, Mao-Fa Fang and Yan-Min Hu

045012 Combined effects of asymmetry and noise correlation on the noise-enhanced stability phenomenon in abistable systemDong-Cheng Mei, Zheng-Lin Jia and Can-Jun Wang

045013 Nonadditivity of quantum capacities of quantum multiple-access channels and the butterfly networkPeng Huang, Guangqiang He, Jun Zhu and Guihua Zeng

045014 Subquantum nonlocal correlations induced by the background random fieldAndrei Khrennikov

045015 Cryptanalysis of quantum secret sharing based on GHZ statesXiao-Fen Liu and Ri-Jing Pan

045016 Scalar field reconstruction of power-law entropy-corrected holographic dark energyEsmaeil Ebrahimi and Ahmad Sheykhi

045017 The chaotic atom model via a fractal approximation of motionM Agop, P Nica, S Gurlui, C Focsa, D Magop and Z Borsos

045018 Three-dimensional quantum key distribution in the presence of several eavesdroppersM Daoud and H Ez-zahraouy




Physica Scripta

Vol 84, No 4 045001–048401

October 2011


www.physica.org

PS84-4cover-UK.indd 2-4 12/10/2011 10:14




Featured in this issueComments on Condensed Matter Physics

PAPERS

GENERAL PHYSICS

035001 Multisoliton interaction in discrete alpha-helical proteins with interspine couplingM M Latha and S S Veni

035002 Coulomb screening of 2D massive Dirac fermionsJia-Ning Zhang

035003 A new generalized fifth-order nonlinear integrable equationAbdul-Majid Wazwaz

035004 Quantum diffusionRoumen Tsekov

035005 Oscillating and rotating boundary conditions in quantum mechanicsCem Yuce and Zalihe Ozcakmakli

035006 Exact analytic solutions generated from stipulated Morse and trigonometric Scarf potentialsN Saikia and S A S Ahmed

035007 Some Lagrangians for systems without a LagrangianM C Nucci and P G L Leach

035008 Noise enhanced stability effect in a metastable system with two different kinds of time delays andcross-correlated noisesZheng-Lin Jia and Dong-Cheng Mei

NUCLEAR PHYSICS

035201 Thermal phase transition in 93−98Mo nucleiZ Kargar and F Mosaleh


035401 Kinetic description of self-field effects on laser and betatron emission in wiggler-pumped ion-channel freeelectron lasersM Alimohamadi, H Mehdian and A Hasanbeigi


035501 Drift-Alfven eigenmodes in inhomogeneous electron–positron–ion plasmasQ Haque, S Yamin and Ali Ahmad

035502 Self-modulation instability of an intense laser beam in a magnetized pair plasmaHua-Ying Chen, San-Qiu Liu and Xiao-Qing Li

035503 Parametric decay of whistler waves in electron magnetohydrodynamicsLennart Stenflo and Gert Brodin

035504 Dynamic evolution of the resistive wall mode in flowing plasmasLongxi Chen and Zhiwei Ma

035505 Acoustic solitons in magnetized quantum electron–positron plasmasS Mahmood, N Akhtar and H Ur-Rehman



Volume 83 Number 3 March 2011

Physica Scripta

Vol 83, No 3 035001–038304

March 2011

Volume 83 Number 3 March 2011

www.physica.org

PS83-3cover-UK.indd 2-4 07/03/2011 08:32




www.physica.org

PAPERS

GENERAL PHYSICS

015001 From the conservation laws to the Hamiltonian structures of discrete soliton systemsJian-bing Zhang, Jie Ji and Yu-qin Yao

015002 Perturbation of dispersive topological solitonsStephen Johnson and Anjan Biswas

015003 Amplification of weak signals via the non-adiabatic regime of stochastic resonance in a bistabledynamical system with time delayLu-Chun Du and Dong-Cheng Mei

015004 l-states of the Manning–Rosen potential with an improved approximate scheme and Feynman pathintegral formalismA Diaf and A Chouchaoui

015005 Accurate analytic approximation to the nonlinear pendulum problemM Turkyilmazoglu

015006 Vibration control for the parametrically excited van der Pol oscillator by nonlocal feedbackAttilio Maccari

015007 New stability and stabilization criteria for fuzzy neural networks with various activation functionsK Mathiyalagan, R Sakthivel and S Marshal Anthoni

015008 The time-dependent forced anisotropic oscillator in noncommutative phase spaceMai-Lin Liang and Qian Chen

015009 Electromagnetic potentials without gauge transformationsA Chubykalo, A Espinoza and R Alvarado Flores

015010 Two schemes of remote preparation of a four-particle entangled W state via a six-qubit maximallyentangled stateXin-Wei Zha and Hai-Yang Song

015011 Stochastic quantization method for spinless relativistic particles in two wave fieldsNadia Chine and Lyazid Chetouani

NUCLEAR PHYSICS

015201 Characteristics of multiplicity distribution of target fragments in forward and backward hemispheres inhigh-energy nucleus–nucleus interactionsDipak Ghosh, Argha Deb and Swarnapratim Bhattacharyya


015301 Resonance transitions in Rh VIII, Pd IX, Ag X and Cd XI spectraA N Ryabtsev and E Ya Kononov

015302 Multiconfiguration Dirac–Fock calculations of transition probabilities of some tungsten ionsFeng Hu, Chuangke Wang, Jiamin Yang, Gang Jiang and Lianghuan Hao


015401 On the interaction between two two-level atoms and a two mode cavity field in the presence of detuningand cross-Kerr nonlinearityN H Abdel-Wahab and M F Mourad



Volume 84 Number 1 July 2011

Physica Scripta

Vol 84, No 1 015001–019802

July 2011

Volume 84 Number 1 July 2011

PS84-1cover-UK.indd 2-4 30/06/2011 10:42




PAPERS

GENERAL PHYSICS

055001 Localized nonlinear wavepackets with radial–azimuthal modulated nonlinearity and an external potentialWei-Ping Zhong, Milivoj R Belic and Gaetano Assanto

055002 Relativistic two-dimensional H-like model atoms in an external magnetic fieldA Poszwa

055003 Thermodynamic functions of fluctuating electromagnetic fields within a heterogeneous systemIllarion Dorofeyev

055004 On Newton’s third law and its symmetry-breaking effectsMario J Pinheiro

055005 The k-essence models and cosmic acceleration in generalized teleparallel gravityM Sharif and Shamaila Rani

055006 Distinct kinds of multiple-soliton solutions for a (3+1)-dimensional generalized B-typeKadomtsev–Petviashvili equationAbdul-Majid Wazwaz

055007 Delay-dependent global asymptotic stability criteria for genetic regulatory networks with time delays inthe leakage termR Rakkiyappan, P Balasubramaniam and K Balachandran

055008 Notes on thermodynamics in special relativityM Przanowski and J Tosiek

ELEMENTARY PARTICLES AND FIELDS

055101 Interaction of orientable object fields with gauge fieldsD M Gitman and A L Shelepin

NUCLEAR PHYSICS

055201 On the determination of the time-scale of three-fragment emission in the 12.7 GeV 4He+238U reactionusing the polycarbonate track detector MakrofolSvetislav Savovic, Zivojin Todorovic, Alexandar Djordjevich and Stevan Jokic


055301 Measurements of hyperfine structure in 51V IIN M R Armstrong, S D Rosner and R A Holt


055401 The eigenvalues and eigenstates of the effective Hamiltonian in the interaction of an atom with bothclassical gravity and quantum radiationM Mohammadi

055402 Bandgap calculation of two-dimensional mixed solid–fluid phononic crystals by Dirichlet-to-NeumannmapsFeng-Lian Li, Yue-Sheng Wang and Chuanzeng Zhang



Volume 84 Number 5 November 2011

Physica Scripta

Vol 84, No 5 055001–059801

November 2011

Volume 84 Number 5 November 2011

www.physica.org

PS84-5cover-UK.indd 2-4 04/11/2011 11:44




PAPERS

GENERAL PHYSICS

045001 Homodyne estimation of quantum state purity by exploiting the covariant uncertainty relationV I Man’ko, G Marmo, A Porzio, S Solimeno and F Ventriglia

045002 The Schmidt number as a universal entanglement measureJ Sperling and W Vogel

045003 Classification of integrable discrete Klein–Gordon modelsIsmagil T Habibullin and Elena V Gudkova

045004 Multiparty quantum secret sharing based on GHZ statesTzonelih Hwang, Cheng-Chieh Hwang and Chuan-Ming Li

045005 Extended Galilean transformations for high-order systems in two integrable hierarchiesDa-jun Zhang, Deng-yuan Chen and Liu-feng Hu

045006 On the spontaneous ordering of the mixed-spin Ising square lattice with singly and triply decorated bondsJ Kissova and J Strecka

045007 Anomalous diffusion in a symbolic modelH V Ribeiro, E K Lenzi, R S Mendes and P A Santoro

045008 Fidelity of structured amplitude-damping channelsJing Wang, Li Jiang, Han Zhang, Hanzhuang Zhang and Liquan Zhang

045009 Nonlinear excitations in a continuous bi-inductance electrical lineFrancois Beceau Pelap, Innocent Tatsinkou and Anaclet Fomethe


045301 The mechanical, electronic structure and thermodynamic properties of B2-based AgRE studied fromfirst-principlesXiaoma Tao, Hongmei Chen, Xingxiu Li, Yifang Ouyang and Shuzhi Liao

045302 The Stark effect in autoionizing doubly excited states of helium below the He+(n = 2) thresholdSpyros I Themelis


045401 Effect of higher-order waves in parametric oscillatory instability in optical cavitiesM Abdi and A R Bahrampour


045501 The 3+1 dimensional Kadomtsev–Petviashvili Burgers’ equation in non-uniform dusty plasmasLi-Ping Zhang, Ju-Kui Xue and Li-Hua Yuan

045502 Transport of fast electrons in lower hybrid current drive plasmas in the HT-7 tokamakZ Y Chen, D Fang, F Dai, Z Q Duan, J X Zhu, W M Sun, B N Wan and Y J Shi

045503 Experimental and theoretical studies of the direct-current breakdown voltage in argon at micrometerseparationsM Klas, S Matejcık, B Radjenovic and M Radmilovic-Radjenovic

CONDENSED MATTER: STRUCTURAL, MECHANICAL AND THERMAL PROPERTIES

045601 Statistical derivation of modified hydrodynamic equations for nanotube flowsI Yu Popov



Volume 83 Number 4 April 2011

Physica Scripta

Vol 83, No 4 045001–047004

April 2011

Volume 83 Number 4 April 2011

www.physica.org

PS83-4cover-UK.indd 2-4 30/03/2011 10:20





PAPERS

GENERAL PHYSICS

025001 Deterministic controlled-phase gate and preparation of cluster states via singly charged quantum dots incavity quantum electrodynamicsTao Yu, Ai-Dong Zhu, Shou Zhang, Kyu-Hwang Yeon and Seong-Cho Yu

025002 A compact discretization of O(h4) for two-dimensional nonlinear triharmonic equationsR K Mohanty, M K Jain and B N Mishra

025003 A scheme for symmetrization verificationPedro Sancho

025004 Scattering and bound state solutions of the asymmetric Hulthen potentialAltug Arda, Oktay Aydogdu and Ramazan Sever

025005 The Dirac–Yukawa problem in view of pseudospin symmetryOktay Aydogdu and Ramazan Sever

025006 Semiclassical aspects and supersymmetry of bound Dirac states for central pseudo-scalar potentialsKarl-Erik Thylwe and Staffan Linnæus

025007 New higher-dimensional fifth-order nonlinear equations with multiple soliton solutionsAbdul-Majid Wazwaz

025008 Synchronization analysis of complex dynamical networks with delayed and non-delayed coupling basedon pinning controlSong Zheng and Qinsheng Bi

025009 The relaxation time of processes in a FitzHugh–Nagumo neural system with time delayAiling Gong, Hua Wang and Chunhua Zeng

025010 The tanh and sine–cosine methods for higher order equations of Korteweg–de Vries typeMarwan Alquran and Kamel Al-Khaled

025011 Hidden rotational symmetry in a generalized Ising model with rectangular symmetryHai-Yao Deng and Kaige Hu


025301 Verification of the validity of the short-pulse approximation for one-dimensional Rydberg atomsT Kopyciuk and M Grajek

025302 Efficient extension of the trapping lifetime of single atoms in an optical tweezer by laser coolingJun He, Baodong Yang, Tiancai Zhang and Junmin Wang


025401 Power-flow formulation of a ray approach to the modelling of inhomogeneous wavesM Tereshchenko, F Castejon, S Pavlov and A Cappa

025402 The deflection of bright spatial solitons in a biased non-centrosymmetric two-photon photovoltaicphotorefractive crystal due to first-order diffusion and higher order driftS Shwetanshumala, S Konar, N Asif and A Biswas

025403 Mixed convection boundary-layer flow about an isothermal solid sphere in a nanofluidL Tham, R Nazar and I Pop



Volume 84 Number 2 August 2011

Physica Scripta

Vol 84, No 2 025001–029701

August 2011

Volume 84 Number 2 August 2011

www.physica.org

PS84-2cover-UK.indd 2-4 05/08/2011 10:08



www.physica.org

PAPERS

GENERAL PHYSICS

065001 Exact solutions of a two-dimensional cubic–quintic discrete nonlinear Schrodinger equationAvinash Khare, Kim Ø Rasmussen, Mogens R Samuelsen and Avadh Saxena

065002 The Anderson localization problem, the Fermi–Pasta–Ulam paradox and the generalized diffusionapproachV N Kuzovkov

065003 Self-similar analytical model of plasma expansion in a magnetic fieldH B Nersisyan, K A Sargsyan, D A Osipyan, M V Sargsyan and H H Matevosyan

065004 Bifurcation and chaos in a perturbed soliton equation with higher-order nonlinearityJun Yu, Rongbo Zhang and Guojuan Jin

065005 On the exact solutions of a nano boundary layer problem using the simplest equation methodAbdelhalim Ebaid and Nader Y Abd Elazem

065006 A pedagogical presentation of a C�-algebraic approach to quantum tomographyA Ibort, V I Man’ko, G Marmo, A Simoni and F Ventriglia

065007 Soliton solutions of the dispersive sine-Gordon and the dispersive sinh-Gordon equations with fourthspatial or spatio-temporal derivativesAbdul-Majid Wazwaz

065008 Analytical treatment of the two-body spinless Salpeter equation with the Hulthen potentialS Zarrinkamar, A A Rajabi, H Hassanabadi and H Rahimov

065009 Generation of a three-dimensional N-atom GHZ state based on optical-fiber-connected cavity quantumelectrodynamicsY Q Zhang, Z Jin, S Zhang, K H Yeon and S C Yu

065010 Entanglement dynamics of two electron-spin qubits in a strongly detuned and dissipativequantum-dot-cavity systemShao-Hua Xiang, Xiao-Peng Deng, Ke-Hui Song, Wei Wen and Zhen-Gang Shi

065011 Impact of the depth of the wells and multifractal analysis on stochastic resonance in a triple-well systemS Arathi and S Rajasekar

065012 Effects of external bounded noise on nonlinear dynamics of plasma densityC Nono Dueyou Buckjohn, M Siewe Siewe, C Tchawoua and T C Kofane


065301 Single-electron capture from helium by fast protonsR Samanta and M Purkait

065302 Studies on the full vibrational energies and dissociation energies of some halogen diatomic moleculesQunchao Fan, Weiguo Sun, Huidong Li and Hao Feng

065303 New even and odd parity levels of neutral praseodymiumT I Syed, I Siddiqui, K Shamim, Z Uddin, G H Guthohrlein and L Windholz


065401 Solitons and their interactions in a tapered aortaLi-hua Zhao, Yue-yue Wang and Chao-qing Dai



Volume 84 Number 6 December 2011

Physica Scripta

Vol 84, No 6 065001–069502

December 2011

Volume 84 Number 6 December 2011A journal of the Royal Swedish Academy of Sciences published by IOP Publishing

PS84-6cover-UK.indd 2-4 01/12/2011 13:21

Volume 83, issue 1Cover image taken from AsiehSadat Kazemi et al 2011 Phys. Scr. 83 015801

Volume 83, issue 5Cover image taken from Madalina Boca and Andreea Oprea 2011 Phys. Scr. 83 055404

Volume 84, issue 3Cover image taken from S Cheng et al 2011 Phys. Scr. 84 035006

Volume 83, issue 2Cover image taken from Yue Zhuo et al 2011 Phys. Scr. 83 025801

Volume 83, issue 6Cover image taken from Ping Liu and Shutang Liu 2011 Phys. Scr. 83 065006

Volume 84, issue 4Cover image taken from Sandip V Kamat et al 2011 Phys. Scr. 84 045801

Volume 83, issue 3Cover image taken from Ram Kripel and Santwana Shukla 2011 Phys. Scr. 83 035702

Volume 84, issue 1Cover image taken from R J Zhou et al 2011 Phys. Scr. 84 015501

Volume 84, issue 5Cover image taken from M A Ahmed et al 2011 Phys. Scr. 84 055602

Volume 83, issue 4Cover image taken from V A Gribkov 2011 Phys. Scr. 83 045606

Volume 84, issue 2Cover image taken from Benjamin J Irving et al 2011 Phys. Scr. 84 028108

Volume 84, issue 6Cover image taken from Donepudi V Rao et al 2011 Phys. Scr. 84 065802

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