Devil's staircases and supersolids in a one-dimensional dipolar Bose gas

F. J. Burnell, Meera M. Parish, N. R. Cooper, and S. L. Sondhi
We consider a single-component gas of dipolar bosons confined in a one-dimensional optical lattice, where the dipoles are aligned such that the long-ranged dipolar interactions are maximally repulsive. In the limit of zero intersite hopping and sufficiently large on-site interaction, the phase diagr ... [Phys. Rev. B 80, 174519 (2009)] published Thu Nov 19, 2009.

Nucleation and first-stage growth processes of extrinsic defects in GaAs triggered by self-interstitials

F. Gala and G. Zollo
The growth process of small self-interstitial clusters I (n<=7) in crystalline GaAs has been addressed by semi-empirical tight-binding molecular-dynamics technique. The I ground-state structures have been found among many possible choices of topological properties and stoichiometric compositions. Th ... [Phys. Rev. B 80, 174113 (2009)] published Thu Nov 19, 2009.

High-pressure Raman and x-ray diffraction studies on LaB

B. K. Godwal, E. A. Petruska, S. Speziale, J. Yan, S. M. Clark et al.
X-ray diffraction measurements and Raman spectroscopy at room temperature document the equation of state and the frequency shifts for E, T, and A vibrational modes of polycrystalline LaB under pressure. The data exhibit smooth pressure dependencies, yielding a zero-pressure isothermal bulk modulus K ... [Phys. Rev. B 80, 172104 (2009)] published Thu Nov 19, 2009.

Stopping of energetic cobalt clusters and formation of radiation damage in graphite

Vladimir N. Popok, Sasa VuCkovic, Juha Samela, Tommi T. Jarvi, Kai Nordlund et al.
The interaction of energetic (up to 200 eV/atom) size-selected Co clusters with HOPG is studied both experimentally and theoretically. Etching of the radiation damaged areas introduced by cluster impacts provides a measure of the depth to which the collision cascades are developed and allows a compa ... [Phys. Rev. B 80, 205419 (2009)] published Thu Nov 19, 2009.

Cooperative mechanism for anchoring highly polar molecules at an ionic surface

J. Schutte, R. Bechstein, M. Rohlfing, M. Reichling, and A. Kuhnle
Structure formation of the highly polar molecule cytosine on the (111) cleavage plane of calcium fluoride is investigated in ultrahigh vacuum using noncontact atomic force microscopy at room temperature. Molecules form well-defined trimer structures, covering the surface as homogeneously distributed ... [Phys. Rev. B 80, 205421 (2009)] published Thu Nov 19, 2009.

Quantum confinement and thermal effects on the Raman spectra of Si nanocrystals

Giuseppe Faraci, Santo Gibilisco, and Agata R. Pennisi
In nanocrystals, first-order Raman spectra can exhibit large shift and width due to two overlapping effects: quantum confinement and thermal heating. In order to distinguish each contribution we studied silicon nanocrystals by Raman spectroscopy. From the measurements we extracted the dependence of ... [Phys. Rev. B 80, 193410 (2009)] published Thu Nov 19, 2009.

Low-temperature observation of the softened C-H stretching vibrations of cyclohexane on Rh(111)

Takanori Koitaya, Atsushi Beniya, Kozo Mukai, Shinya Yoshimoto, and Jun Yoshinobu
The C-H stretching vibrations of cyclohexane on Rh(111) were investigated using infrared reflection absorption spectroscopy between 20 and 89 K. At 20 K, the softened C-H stretching band consists of several sharp peaks, ranging from 2500 to 2700 cm. The wide-range distribution of the softened C-H s ... [Phys. Rev. B 80, 193409 (2009)] published Thu Nov 19, 2009.

Stabilization of large silicon fullerenes and related nanostructures through puckering and poly(oligo)merization

Aristides D. Zdetsis
The structure, symmetry, and stability of large SiH, n=60, 70, 76, 80, and 180 cages and the SiH ligomers: SiH, SiH, and SiH, together with some related fullerenes and nanostructures, are studied by ab initio density functional theory and second order Moller-Plesset perturbation theory (for SiH). It ... [Phys. Rev. B 80, 195417 (2009)] published Thu Nov 19, 2009.

Phonon density of states and heat capacity of LaTe

O. Delaire, A. F. May, M. A. McGuire, W. D. Porter, M. S. Lucas et al.
The phonon density of states (DOS) of LaTe compounds (x=0.0,0.18,0.32) was measured at 300, 520, and 780 K, using inelastic neutron scattering. A significant stiffening of the phonon DOS and a large broadening of features were observed upon introduction of vacancies on La sites (increasing x). Heat- ... [Phys. Rev. B 80, 184302 (2009)] published Thu Nov 19, 2009.

Extension of the RosencwaigGershoFernelius photothermal deflection spectroscopy model to account for multiple reflections in epitaxial samples

I. C. W. Chan and M. Beaudoin
The Fernelius extension to the RosencwaigGersho theory for photothermal deflection spectroscopy (PDS) is modified to take into account multiple reflections and light trapping within a thin film-on-substrate system where both the thin film and the substrate can be absorbing. The extended model is use ... [J. Appl. Phys. 106, 103510 (2009)] published Thu Nov 19, 2009.

The Debye-like relaxation mechanism in poly(vinylidene fluoride-trifluoroethylene) ferroelectric polymers

P. F. Liu, P. Gemeiner, X. J. Meng, J. H. Chu, S. Geiger et al.
In this work we studied 65-nm-thick poly(vinylidene fluoride-trifluoroethylene) ferroelectric polymers films grown by LangmuirBlodgett onto silicon substrates. Three dielectric anomalies have been unambiguously evidenced. The high temperature one near 380 K corresponds to the ferroelectric-paraelect ... [J. Appl. Phys. 106, 104113 (2009)] published Thu Nov 19, 2009.

Computational study of thermocompression bonding of carbon nanotubes to metallic substrates

Xiaohui Song, Zhiyin Gan, Sheng Liu, Han Yan, and Qiang Lv
Thermocompression bonding of carbon nanotubes (CNTs) to metallic substrates is studied using molecular dynamics. The interaction of the CNT and the metal cluster at high temperature is investigated first. For the diffusion bonding process, the effects of temperature and external pressure are examine ... [J. Appl. Phys. 106, 104308 (2009)] published Thu Nov 19, 2009.

Adsorption of Ar on planar surfaces studied with a density functional theory

Salvador A. Sartarelli and Leszek Szybisz
The adsorption of Ar on planar structureless substrates of alkali metals, alkaline-earth metal Mg, CO, and Au was analyzed by applying a density functional formalism which includes a recently proposed effective attractive pair potential conditioned to Ar. It is shown that this approach reproduces th ... [Phys. Rev. E 80, 052602 (2009)] published Thu Nov 19, 2009.

A molecular dynamics study of the influence of ionic charge distribution on the dynamics of a molten salt

Hualin Li and Mark N. Kobrak
The distribution of charge in an ion of a fused salt is known to be an important determinant of liquid dynamics. However, the details of this relationship remain poorly understood. We present the results of molecular dynamics simulations on a model molten salt system and show that changes in the dis ... [J. Chem. Phys. 131, 194507 (2009)] published Thu Nov 19, 2009.

Swelling and collapse of polyelectrolyte gels in equilibrium with monovalent and divalent electrolyte solutions

De-Wei Yin, Monica Olvera de la Cruz, and Juan J. de Pablo
The swelling of polyelectrolyte (PE) gels by 1:1 and 2:1 salts is studied via osmotic ensemble Monte Carlo simulations at constant osmotic pressure and electrolyte chemical potential of a reservoir phase in equilibrium with a model PE network. Large molecular weight gels exhibit a remarkable swellin ... [J. Chem. Phys. 131, 194907 (2009)] published Thu Nov 19, 2009.

Localized soft modes and the supercooled liquid's irreversible passage through its configuration space

Asaph Widmer-Cooper, Heidi Perry, Peter Harrowell, and David R. Reichman
Using computer simulations, we show that the localized low frequency normal modes of a configuration in a supercooled liquid are strongly correlated with the irreversible structural reorganization of the particles within that configuration. Establishing this correlation constitutes the identificatio ... [J. Chem. Phys. 131, 194508 (2009)] published Thu Nov 19, 2009.

Publisher's Note: Transition state analysis of solid-solid transformations in nanocrystals [J. Chem. Phys. 131, 164116 (2009)]

Michael Grunwald and Christoph Dellago
Abstract not available. [J. Chem. Phys. 131, 199901 (2009)] published Thu Nov 19, 2009.

Dynamical and quasistatic structural relaxation paths in PdNiP glass

A. Kahl, T. Koeppe, D. Bedorf, R. Richert, M. L. Lind et al.
By sequential heat treatment of a PdNiP metallic glass at temperatures and durations for which alpha-relaxation is not possible, dynamic, and quasistatic relaxation paths below the glass transition are identified via ex situ ultrasonic measurements following each heat treatment. The dynamic relaxati ... [Appl. Phys. Lett. 95, 201903 (2009)] published Thu Nov 19, 2009.

Superhydrophobic floatability of a hydrophilic object driven by edge effect

Feng-Ming Chang, Yu-Jane Sheng, and Heng-Kwong Tsao
It is generally believed that a water-repellent surface is necessary for small insects to stand on water. Through a combined experimental and theoretical study, we demonstrate that an object with hydrophilic surface can float with apparent contact angle greater than 90 degrees due to edge effect. T ... [Appl. Phys. Lett. 95, 204107 (2009)] published Thu Nov 19, 2009.

Photoluminescence enhancement of Er-doped silica containing Ge nanoclusters

J. Guzman, S. J. Shin, C. Y. Liao, C. W. Yuan, P. R. Stone et al.
The photoluminescence (PL) of Er-doped silica films containing Ge nanoclusters synthesized by ion implantation was investigated. The area of the 1540 nm Er PL peak was enhanced by up to a factor of 200 by the addition of Ge nanoclusters. The PL enhancement was found to be proportional to the concent ... [Appl. Phys. Lett. 95, 201904 (2009)] published Thu Nov 19, 2009.

Inaccuracy of Density Functional Theory Calculations for Dihydrogen Binding Energetics onto Ca Cation Centers

Janghwan Cha, Seokho Lim, Cheol Ho Choi, Moon-Hyun Cha, and Noejung Park
We investigate the mechanism of dihydrogen adsorption onto Ca cation centers, which has been the significant focus of recent research for hydrogen storage. We particularly concentrate on reliability of commonly used density-functional theories, in comparison with correlated wave function theories. I ... [Phys. Rev. Lett. 103, 216102 (2009)] published Thu Nov 19, 2009.

Grain Growth Enhancement and Ga Distribution of Cu(InGa)Se Film Using CuSe Layer on CuInGa Metal Precursor

Min Sik Kim, R. B. V. Chalapathy, Kyung Hoon Yoon, and Byung Tae Ahn
A precursor layer for Cu(InGa)Se (CIGS) was deposited by simultaneous sputtering of CuIn and CuGa and subsequent sputtering of CuSe. The CuSe/metal alloy-stacked precursor was selenized at 550 degrees C in a Se vapor atmosphere to grow a CIGS film. The thickness of the CuSe layer was varied to contr ... [J. Electrochem. Soc. 157, B154 (2009)] published Wed Nov 18, 2009.

Extended excitons and compact heliumlike biexcitons in type-II quantum dots

Bhavtosh Bansal, S. Godefroo, M. Hayne, G. Medeiros-Ribeiro, and V. V. Moshchalkov
We have used magnetophotoluminescence measurements to establish that InP/GaAs quantum dots have a type-II (staggered) band alignment. The average excitonic Bohr radius and the binding energy are estimated to be 15 nm and 1.5 meV, respectively. When compared to bulk InP, the excitonic binding is weak ... [Phys. Rev. B 80, 205317 (2009)] published Wed Nov 18, 2009.

Antibonding plasmon mode coupling of an individual hole in a thin metallic film

J. W. Lee, T. H. Park, Peter Nordlander, and Daniel M. Mittleman
The polarization dependence of the optical properties of individual subwavelength holes in a thin metallic film is studied using terahertz time-domain spectroscopy. We show that for parallel polarization of the incident light, the coupling is predominantly to short-range bonding film plasmons while ... [Phys. Rev. B 80, 205417 (2009)] published Wed Nov 18, 2009.

Ultranarrow coupling-induced transparency bands in hybrid plasmonic systems

Thomas Zentgraf, Shuang Zhang, Rupert F. Oulton, and Xiang Zhang
Plasmons in nanoscale structures represent an exciting new route toward efficient manipulation of photons, especially at subwavelength scales. Of particular interest are the hybridized plasmonic systems, in which the interaction among the plasmonic elements can be utilized to tailor the optical resp ... [Phys. Rev. B 80, 195415 (2009)] published Wed Nov 18, 2009.

Changing the physical and chemical properties of titanium oxynitrides TiNO by changing the composition

Jesus Graciani, Said Hamad, and Javier Fdez. Sanz
The stability and structural properties of titanium oxynitrides, TiNO, of different compositions are theoretically analyzed by means of first-principles periodic density-functional calculations. We show that at x=0.550.6 there is a change in the preferred structure from that of NaCl type to the alph ... [Phys. Rev. B 80, 184112 (2009)] published Wed Nov 18, 2009.

3d transition metal impurities in aluminum: A first-principles study

M. Mantina, S. L. Shang, Y. Wang, L. Q. Chen, and Z. K. Liu
In this work, appropriate description of interactions of 3d transition metals in aluminum (Al-3d) is attained from first-principles using LDA+U potential within density-functional theory. By reproducing diffusion coefficients of 3d transition metals in aluminum in agreement with reliable data from e ... [Phys. Rev. B 80, 184111 (2009)] published Wed Nov 18, 2009.

Selection-rule blockade and rectification in quantum heat transport

Teemu Ojanen
We present a thermal transport phenomenon, a unidirectional selection-rule blockade, and show how it produces unprecedented rectification of bosonic heat flow through molecular or mesoscopic quantum systems. Rectification arises from the quantization of energy levels of the conduction element and se ... [Phys. Rev. B 80, 180301 (2009)] published Wed Nov 18, 2009.

Effects of methanol on nanoparticle self-assembly at liquid-liquid interfaces: A molecular dynamics approach

Mingxiang Luo, Yanmei Song, and Lenore L. Dai
Molecular dynamics simulations have been performed to study the influence of methanol on the self-assembly of nanoparticles at liquid-liquid interfaces. The simulation shows that the methanol molecules, at low volume fraction, stay in the aqueous phase but with a preference of the water-trichloroeth ... [J. Chem. Phys. 131, 194703 (2009)] published Wed Nov 18, 2009.

Extrinsic curvature, geometric optics, and lamellar order on curved substrates

Randall D. Kamien, David R. Nelson, Christian D. Santangelo, and Vincenzo Vitelli
When thermal energies are weak, two-dimensional lamellar structures confined on a curved substrate display complex patterns arising from the competition between layer bending and compression in the presence of geometric constraints. We present broad design principles to engineer the geometry of the ... [Phys. Rev. E 80, 051703 (2009)] published Wed Nov 18, 2009.

Visualization of highly graded oxygen vacancy profiles in lead-zirconate-titanate by spectrally resolved cathodoluminescence spectroscopy

Atsuo Matsutani, Zhenhua (Jerry) Luo, Soodkhet Pojprapai, Mark Hoffman, and Giuseppe Pezzotti
The ultraviolet and visible cathodoluminescence (CL) emitted at room temperature from bulk hard lead-zirconate-titanate polycrystalline perovskite has been systematically collected before and after an annealing cycle conducted in a reducing atmosphere. Spectroscopic assessments have been made of the ... [Appl. Phys. Lett. 95, 202903 (2009)] published Wed Nov 18, 2009.

Shape-dependent nonlinear absorption and relaxation in CuInS nanocrystals

N. Venkatram, Sudip K. Batabyal, Lu Tian, Jagadese J. Vittal, and Wei Ji
We report the observation of nonlinear-optical response and relaxation in copper indium sulfide (CuInS) crystalline nanoparticles and nanorods with femtosecond Z-scans and transient absorption measurements. Dependent on the size and shape, two-photon absorption and saturation in the one-photon absor ... [Appl. Phys. Lett. 95, 201109 (2009)] published Wed Nov 18, 2009.

Strength of lithium fluoride under shockless compression to 114 GPa

T. Ao, M. D. Knudson, J. R. Asay, and J.-P. Davis
A magnetic loading technique was used to ramp load single-crystal [100] lithium fluoride specimens to peak stresses of 5114 GPa. Wave analysis of in situ particle velocity profiles was used to estimate the compressive strength of LiF at peak stress. It was found that the strength increased with peak ... [J. Appl. Phys. 106, 103507 (2009)] published Wed Nov 18, 2009.

GeSbTe thin films deposited by pulsed laser: An ellipsometry and Raman scattering spectroscopy study

P. Nemec, A. Moreac, V. Nazabal, M. Pavlista, J. Prikryl et al.
Pulsed laser (532 nm) deposited GeSbTe thin films were investigated by means of spectroscopic ellipsometry and Raman scattering spectroscopy. TaucLorentz and CodyLorentz models were employed for the evaluation of optical functions of thin films in as-deposited (amorphous) and crystalline (cubic) pha ... [J. Appl. Phys. 106, 103509 (2009)] published Wed Nov 18, 2009.

Enhancement of light transmission by coupling to surface plasmon polaritons of a layer-plus-islands silver layer

Pangpang Wang, Dongyan Zhang, Dong Hun Kim, Zhiyong Qiu, Lumei Gao et al.
Enhanced light transmission through coupling incident light with surface plasmon polaritons (SPPs) on a layer-plus-islands nanostructure Ag layer, surrounded by symmetric ZnO dielectrics (ZnO/Ag/ZnO), was investigated. The couple and decouple processes at ZnO/Ag and Ag/ZnO grating interfaces were co ... [J. Appl. Phys. 106, 103104 (2009)] published Wed Nov 18, 2009.

Energy transfer rates and population inversion of I excited state of Er investigated by means of numerical solutions of the rate equations system in Er:LiYF crystal

Laercio Gomes, Andre Felipe Henriques Librantz, Fabio Henrique Jagosich, Wonder Alexandre Luz Alves, Izilda Marcia Ranieri et al.
In this work, we present the spectroscopic properties of LiYF (YLF) single crystals activated by high doping of erbium ions. The most important processes that lead to the up-conversion erbium emissions in the infrared region were identified. A time-resolved luminescence spectroscopy technique was em ... [J. Appl. Phys. 106, 103508 (2009)] published Wed Nov 18, 2009.

Influence of annealing and Ag doping on structural and optical properties of indium tin oxide thin films

Chun-Bin Cao, Lei Xiao, Xue-Ping Song, and Zhao-Qi Sun
Indium tin oxide (ITO) and Ag (1.20.1 at. %)-ITO films with the thickness of 130 nm were deposited on glass substrates at room temperature by dc magnetron sputtering and postannealed at the temperature range of 200400 degrees C. By calculating the x-ray diffraction data, the lattice constants o ... [J. Vac. Sci. Technol. A 28, 48 (2009)] published Wed Nov 18, 2009.

Bose-Einstein Condensation in Quantum Glasses

Giuseppe Carleo, Marco Tarzia, and Francesco Zamponi
The role of geometrical frustration in strongly interacting bosonic systems is studied with a combined numerical and analytical approach. We demonstrate the existence of a novel quantum phase featuring both Bose-Einstein condensation and spin-glass behavior. The differences between such a phase and ... [Phys. Rev. Lett. 103, 215302 (2009)] published Wed Nov 18, 2009.

Adams and Olmsted Reply:

J. M. Adams and P. D. Olmsted
A Reply to the Comment by Shi-Qing Wang. ... [Phys. Rev. Lett. 103, 219802 (2009)] published Wed Nov 18, 2009.

Comment on Nonmonotonic Models are Not Necessary to Obtain Shear Banding Phenomena in Entangled Polymer Solutions

Shi-Qing Wang
A Comment on the Letter by J. M. Adams and P. D. Olmsted, Phys. Rev. Lett. 102, 067801 (2009). The authors of the Letter offer a Reply. ... [Phys. Rev. Lett. 103, 219801 (2009)] published Wed Nov 18, 2009.

Spin mapping at the nanoscale and atomic scale

Roland Wiesendanger
The direct observation of spin structures with atomic-scale resolution, a long-time dream in condensed matter research, recently became a reality based on the development of spin-sensitive scanning probe methods, such as spin-polarized scanning-tunneling microscopy (SP-STM) and magnetic exchange for ... [Rev. Mod. Phys. 81, 1495 (2009)] published Wed Nov 18, 2009.

Subpicosecond coherent nonlinear optical response of isolated single-walled carbon nanotubes

S. Tao, Y. Miyata, K. Yanagi, H. Kataura, and H. Okamoto
We report an excitation-energy dependence of ultrafast changes of exciton absorptions in isolated semiconducting single-walled carbon nanotubes. For a photoexcitation far below the exciton transition, a blueshift of exciton absorptions originating from the optical Stark effect due to exciton-photon ... [Phys. Rev. B 80, 201405 (2009)] published Tue Nov 17, 2009.

Azobenzene at coinage metal surfaces: Role of dispersive van der Waals interactions

Erik R. McNellis, Jorg Meyer, and Karsten Reuter
We use different semiempirical dispersion correction schemes to assess the role of long-range van der Waals interactions in the adsorption of the prototypical molecular switch azobenzene (CH-N-CH) at the coinage metal surfaces Cu(111), Ag(111), and Au(111). Compared to preceding density-functional t ... [Phys. Rev. B 80, 205414 (2009)] published Tue Nov 17, 2009.

Atomic nature of the Si-B4 paramagnetic center assessed by multifrequency electron spin resonance

K. Keunen and A. Stesmans
An electron spin resonance (ESR) study has been carried out in the range 4.2120 K on the trigonal Si-B4 center in annealed (200350 degrees C) neutron-irradiated p-type Si. Detailed observations reveal a rich Si hyperfine (hf) structure, indicating interaction of the unpaired electron with up to fiv ... [Phys. Rev. B 80, 195207 (2009)] published Tue Nov 17, 2009.

Temperature dependence of the electronic structure of the J=(1/2) Mott insulator SrIrO studied by optical spectroscopy

S. J. Moon, Hosub Jin, W. S. Choi, J. S. Lee, S. S. A. Seo et al.
We investigated the temperature-dependent evolution of the electronic structure of the J=(1/2) Mott insulator SrIrO using optical spectroscopy. The optical conductivity spectra sigma(omega) of this compound has recently been found to exhibit two d-d transitions associated with the transition between ... [Phys. Rev. B 80, 195110 (2009)] published Tue Nov 17, 2009.

Gradient elasticity and flexural wave dispersion in carbon nanotubes

Harm Askes and Elias C. Aifantis
Higher-order elasticity theories have recently been used to predict the dispersion characteristics of flexural waves in carbon nanotubes (CNTs). In particular, nonlocal elasticity and gradient elasticity (with unstable strain gradients) have been employed within the framework of classical Euler-Bern ... [Phys. Rev. B 80, 195412 (2009)] published Tue Nov 17, 2009.

Theory of dynamical scattering in near-edge electron energy loss spectroscopy

C. Witte, S. D. Findlay, M. P. Oxley, J. J. Rehr, and L. J. Allen
Beyond chemical information, the fine structure of an absorption edge gives bonding and electronic information. We provide a synthesis of fine structure and dynamical scattering theory, allowing the exploration of the effects of dynamical scattering on the measured fine structure. We discuss the eff ... [Phys. Rev. B 80, 184108 (2009)] published Tue Nov 17, 2009.

Driving-induced crossover in the avalanche criticality of martensitic transitions

Eduard Vives, Daniel Soto-Parra, Lluis Manosa, Ricardo Romero, and Antoni Planes
An experimental study of the statistical distribution of acoustic emission avalanches in martensitic transitions is presented. The critical exponents characterizing the power-law distributions of avalanches are measured as a function of cycling under soft-driving (stress-driving) and hard-driving (s ... [Phys. Rev. B 80, 180101 (2009)] published Tue Nov 17, 2009.

Phase diagram and critical behavior of the square-lattice Ising model with competing nearest-neighbor and next-nearest-neighbor interactions

Junqi Yin and D. P. Landau
Using the parallel tempering algorithm and graphics processing unit accelerated techniques, we have performed large-scale Monte Carlo simulations of the Ising model on a square lattice with antiferromagnetic (repulsive) nearest-neighbor and next-nearest-neighbor interactions of the same strength and ... [Phys. Rev. E 80, 051117 (2009)] published Tue Nov 17, 2009.

Large radiation fields from nonlocal interaction between terahertz waves and quantum wells with an applied electric field

Guanghui Wang and Qi Guo
The effects of pump intensities and applied electric fields on radiation fields excited by the nonlocal interaction between terahertz waves and AlGaAs/GaAs quantum wells (QWs) are investigated. The numerical results show the resonant radiation fields are very large in the confinement direction, and ... [J. Appl. Phys. 106, 103506 (2009)] published Tue Nov 17, 2009.

Scanning capacitance microscopy studies of unintentional doping in epitaxial lateral overgrowth GaN

J. Sumner, R. A. Oliver, M. J. Kappers, and C. J. Humphreys
Four samples were grown by epitaxial lateral overgrowth (ELOG) using different magnesium precursor fluxes during the coalescence stage. These samples were studied in cross section using scanning capacitance microscopy and scanning electron microscopy. The resulting images revealed the existence of s ... [J. Appl. Phys. 106, 104503 (2009)] published Tue Nov 17, 2009.

Study of acoustic wave behavior in silicon-based one-dimensional phononic-crystal plates using harmony response analysis

Xuefeng Zhu (&#x795D;&#x96EA;&#x4E30;), Tao Xu (&#x5F90;&#x6D9B;), Shengchun Liu (&#x5218;&#x76DB;&#x6625;), and Jianchun Cheng (&#x7A0B;&#x5EFA;&#x6625;)
We promote an efficient method named harmony response analysis (HRA) as a comparison with transient response analysis and supercell plane wave expansion (supercell PWE) to study the behavior of Lamb wave in silicon-based one-dimensional composite plates. To implement HRA for dealing with Lamb waves ... [J. Appl. Phys. 106, 104901 (2009)] published Tue Nov 17, 2009.

Vibration analysis of nanoplates under uniaxial prestressed conditions via nonlocal elasticity

T. Murmu and S. C. Pradhan
In this article, nonlocal elasticity theory is applied to investigate the vibration response of nanoplates under uniaxially prestressed conditions. Nonlocal elasticity theory takes into account the small-size effects when dealing with nanostructures. Nonlocal governing equations of the prestressed n ... [J. Appl. Phys. 106, 104301 (2009)] published Tue Nov 17, 2009.

SnO nanoparticles embedded in silica by ion implantation followed by thermal oxidation

M. A. Tagliente, V. Bello, G. Pellegrini, G. Mattei, P. Mazzoldi et al.
Nanoparticles of tin dioxide embedded in silica matrix were synthesized by ion implanting a Sn ion beam in a silica slide and by annealing in oxidizing atmosphere at 800 degrees C. A detailed structural and optical characterization was performed by using glancing incidence x-ray diffraction, transm ... [J. Appl. Phys. 106, 104304 (2009)] published Tue Nov 17, 2009.

Pressure-induced spin reorientation in LaSr(MnRu)O (y=0 and 0.075) single crystals

K. Mydeen, S. Arumugam, P. Mandal, A. Murugeswari, C. Sekar et al.
The effect of hydrostatic pressure (P) and external magnetic field on the c-axis resistivity (rho) and in-plane ac susceptibility (chi) of LaSr(MnRu)O (y=0 and 0.075) single crystals have been investigated. The ferromagnetic transition temperature (T) increases, while the conductivity decreases, wit ... [J. Appl. Phys. 106, 103908 (2009)] published Tue Nov 17, 2009.

Light absorption in silicon quantum dots embedded in silica

S. Mirabella, R. Agosta, G. Franzo, I. Crupi, M. Miritello et al.
The photon absorption in Si quantum dots (QDs) embedded in SiO has been systematically investigated by varying several parameters of the QD synthesis. Plasma-enhanced chemical vapor deposition (PECVD) or magnetron cosputtering (MS) have been used to deposit, upon quartz substrates, single layer, or ... [J. Appl. Phys. 106, 103505 (2009)] published Tue Nov 17, 2009.

Origin of translocation barriers for polyelectrolyte chains

Rajeev Kumar and M. Muthukumar
For single-file translocations of a charged macromolecule through a narrow pore, the crucial step of arrival of an end at the pore suffers from free energy barriers, arising from changes in intrachain electrostatic interaction, distribution of ionic clouds and solvent molecules, and conformational e ... [J. Chem. Phys. 131, 194903 (2009)] published Tue Nov 17, 2009.

Fluorescence depolarization in poly[2-methoxy-5-((2-ethylhexyl)oxy)-1,4-phenylenevinylene]: Sites versus eigenstates hopping

Jaykrishna Singh, Eric R. Bittner, David Beljonne, and Gregory D. Scholes
We report upon a theoretical study of singlet exciton migration and relaxation within a model conjugated polymer chain. Starting from poly[2-methoxy-5-((2-ethylhexyl)oxy)-1,4-phenylenevinylene] polymer chains, we assume that the pi-conjugation is disrupted by conformational disorder of the chain its ... [J. Chem. Phys. 131, 194905 (2009)] published Tue Nov 17, 2009.

Free energy landscape for the translocation of polymer through an interacting pore

Li-Zhen Sun, Wei-Ping Cao, and Meng-Bo Luo
Free energy landscapes for polymer chain translocating through an interacting pore are calculated by using exact enumeration method. A potential barrier exists at weak attractive or repulsive polymer-pore interaction and it changes to a potential well with the increase in the attraction. The result ... [J. Chem. Phys. 131, 194904 (2009)] published Tue Nov 17, 2009.

Stability of binary mixtures in electric field gradients

Sela Samin and Yoav Tsori
We consider the influence of electric field gradients on the phase behavior of nonpolar binary mixtures. Small fields give rise to smooth composition profiles, whereas large enough fields lead to a phase-separation transition. The critical field for demixing as well as the equilibrium phase-separati ... [J. Chem. Phys. 131, 194102 (2009)] published Tue Nov 17, 2009.

Measurement of anharmonicity of phonons in the negative thermal expansion compound Zn(CN) by high pressure inelastic neutron scattering

R. Mittal, S. L. Chaplot, and H. Schober
Zn(CN) is known to have an isotropic negative thermal expansion (NTE) coefficient (about 51 x 10 K) over 10370 K that is twice as large as that of ZrWO. We have measured the pressure dependence of the phonon spectra up to 30 meV from a polycrystalline sample of Zn(CN) at pressures of 0, 0.3, 1.9, a ... [Appl. Phys. Lett. 95, 201901 (2009)] published Mon Nov 16, 2009.

Calculated properties of fully hydrogenated single layers of BN, BCN, and graphene: Graphane and its BN-containing analogues

Frank W. Averill, James R. Morris, and Valentino R. Cooper
Carbon is an attractive material for hydrogen adsorption due to its light weight, variety of structures, and ability to both physisorb and chemisorb hydrogen. Recently, fully hydrogenated graphene layers (graphane) have been predicted to exist [J. O. Sofo et al., Phys. Rev. B 75, 15340 (2007)], and ... [Phys. Rev. B 80, 195411 (2009)] published Mon Nov 16, 2009.

Hydrogen diffusion in GaAsN

R. Trotta, D. Giubertoni, A. Polimeni, M. Bersani, M. Capizzi et al.
Hydrogen (or deuterium) incorporation in dilute nitride semiconductors modifies dramatically the electronic and structural properties of the crystal through the creation of nitrogen-hydrogen complexes. In this work, we investigate how the formation and dissociation of such complexes rule the diffusi ... [Phys. Rev. B 80, 195206 (2009)] published Mon Nov 16, 2009.

Pressure dependence of the large-scale structure of water

A. Cunsolo, F. Formisano, C. Ferrero, F. Bencivenga, and S. Finet
We report on small-angle x-ray scattering measurements on liquid water aimed at characterizing the pressure evolution of its large-scale structure. Diffraction profiles have been fitted assuming a Lorentzian dependence on the exchanged momentum. As a result, we observe an anomalous behavior of the d ... [J. Chem. Phys. 131, 194502 (2009)] published Mon Nov 16, 2009.

Numerical determination of the exponents controlling the relationship between time, length, and temperature in glass-forming liquids

Chiara Cammarota, Andrea Cavagna, Giacomo Gradenigo, Tomas S. Grigera, and Paolo Verrocchio
There is a certain consensus that the very fast growth of the relaxation time tau occurring in glass-forming liquids on lowering the temperature must be due to the thermally activated rearrangement of correlated regions of growing size. Even though measuring the size of these regions has defied scie ... [J. Chem. Phys. 131, 194901 (2009)] published Mon Nov 16, 2009.

Improvement of the ab initio embedded cluster method for luminescence properties of doped materials by taking into account impurity induced distortions: The example of YO:Bi

Florent Real, Belen Ordejon, Valerie Vallet, Jean-Pierre Flament, and Joel Schamps
New ab initio embedded-cluster calculations devoted to simulating the electronic spectroscopy of Bi impurities in YO sesquioxide for substitutions in either S or C cationic sites have been carried out taking special care of the quality of the environment. A considerable quantitative improvement with ... [J. Chem. Phys. 131, 194501 (2009)] published Mon Nov 16, 2009.

Theory for the three-dimensional Mercedes-Benz model of water

Alan Bizjak, Tomaz Urbic, Vojko Vlachy, and Ken A. Dill
The two-dimensional Mercedes-Benz (MB) model of water has been widely studied, both by Monte Carlo simulations and by integral equation methods. Here, we study the three-dimensional (3D) MB model. We treat water as spheres that interact through Lennard-Jones potentials and through a tetrahedral Gaus ... [J. Chem. Phys. 131, 194504 (2009)] published Mon Nov 16, 2009.

Ferroelectric order stability in the BiPbFeO solid solution

J. Chaigneau, R. Haumont, and J. M. Kiat
Ferroelectric properties of BiPbFeO, through a structural approach, by structural Rietveld refinement and x-ray diffraction versus temperature have been carried out. This study allows us to draw a phase diagram for the system BiPbFeO. Although lead atom gets a lone pair and is commonly understood as ... [Phys. Rev. B 80, 184107 (2009)] published Mon Nov 16, 2009.

Fast-ion conduction and flexibility and rigidity of solid electrolyte glasses

M. Micoulaut, M. Malki, D. I. Novita, and P. Boolchand
Electrical conductivity of dry, slow cooled (AgPO)(AgI) glasses is examined as a function of temperature, frequency, and glass composition. From these data compositional trends in activation energy for conductivity E(x), Coulomb energy E(x) for Ag ion creation, Kohlrausch stretched exponent beta(x), ... [Phys. Rev. B 80, 184205 (2009)] published Mon Nov 16, 2009.

Zero-point divacancy concentration in the shadow wave function model for solid He

R. Pessoa, M. de Koning, and S. A. Vitiello
We address the issue of interaction between zero-point vacancies in solid He as described within the shadow wave function model. Applying the reversible-work method and taking into account finite-size effects, we obtain a zero-point monovacancy concentration of (2.030.02) x 10, which is slightly hig ... [Phys. Rev. B 80, 172302 (2009)] published Mon Nov 16, 2009.