Interaction effects in the optical conductivity of bilayer graphene: Drude-interband coupling and screening
Wang-Kong Tse and A. H. MacDonald
We present a theory of the influence of band renormalization and excitonic electron-electron interaction effects on the optical conductivity sigma(omega) of doped bilayer graphene. Using the Keldysh formalism, we derive a kinetic equation from which we extract numerical and approximate analytic resu ... [Phys. Rev. B 80, 195418 (2009)] published Fri Nov 20, 2009.
Electric and Magnetic Dipole Coupling in Near-Infrared Split-Ring Metamaterial Arrays
Ivana Sersic, Martin Frimmer, Ewold Verhagen, and A. Femius Koenderink
We present experimental observations of strong electric and magnetic interactions between split ring resonators (SRRs) in metamaterials. We fabricated near-infrared planar metamaterials with different inter-SRR spacings along different directions. Our transmission measurements show blueshifts and re ... [Phys. Rev. Lett. 103, 213902 (2009)] published Fri Nov 20, 2009.
Dynamic Length-Scale Characterization and Nonequilibrium Statistical Mechanics of Transport in Open-Cell Foams
Tyler R. Brosten, Sarah L. Codd, Robert S. Maier, and Joseph D. Seymour
Nuclear magnetic resonance measurements of scale dependent dynamics in a random solid open-cell foam reveal a characteristic length scale for transport processes in this novel type of porous medium. These measurements and lattice Boltzmann simulations for a model foam structure indicate dynamical be ... [Phys. Rev. Lett. 103, 218001 (2009)] published Fri Nov 20, 2009.
Photoinduced spin-polarized current in InSb-based structures
M. Frazier, J. G. Cates, J. A. Waugh, J. J. Heremans, M. B. Santos et al.
We demonstrate the observation of spin-polarized photocurrent in InSb films grown on GaAs and InP substrates and InSb quantum wells where a nonequilibrium spin population has been achieved by using circularly polarized radiation. The characteristics of our observations indicated that the circular ph ... [J. Appl. Phys. 106, 103513 (2009)] published Fri Nov 20, 2009.
Metal-semiconductor transition in epitaxial ZnO thin films
M. Nistor, F. Gherendi, N. B. Mandache, C. Hebert, J. Perriere et al.
We report on the formation and transport properties of ZnO thin films which are grown by pulsed-electron beam deposition under a low residual oxygen pressure (10 mbar). ZnO films presenting metallic conductivity at room temperature, and a metal-semiconductor transition at low temperature, were epit ... [J. Appl. Phys. 106, 103710 (2009)] published Fri Nov 20, 2009.
A method for evaluating the ground state excitonic band gaps of strained InGaN/GaN quantum wells
T. K. Sharma and E. Towe
A simple method for calculating the ground state excitonic band gaps of strained wurtzite InGaN/GaN quantum wells (QWs) for the entire composition range is proposed. The modification of the electronic band structure due to strain becomes significant for high values of indium concentration. It is obs ... [J. Appl. Phys. 106, 104509 (2009)] published Fri Nov 20, 2009.
Thermal stability and vibrational spectroscopy of NO shallow donor centers in silicon
Hans Christian Alt and Hans Edwin Wagner
NO-related shallow donors in nitrogen-doped Czochralski silicon have been studied by infrared spectroscopy. Quasithermal equilibrium states were established by long-term thermal annealing in the temperature range from 600 to 1000 degrees C. By quantitative analysis of the 1s-->2p far-infrared el ... [J. Appl. Phys. 106, 103511 (2009)] published Fri Nov 20, 2009.
Zinc and oxygen vacancies in ZnO nanorods
A. Travlos, N. Boukos, C. Chandrinou, Ho-Sang Kwack, and Le Si Dang
Nominally undoped ZnO nanorods, which have been grown with intentionally incorporated large concentrations of zinc and oxygen vacancies, are studied with electron microscopy and photoluminescence spectroscopy at low temperature. Detailed photoluminescence studies reveal that the concentration of the ... [J. Appl. Phys. 106, 104307 (2009)] published Thu Nov 19, 2009.
Publisher's Note: On the kinetics of the Al+Cl reaction: Cluster degradation in consecutive steps [J. Chem. Phys. 131, 174304 (2009)]
Matthias Olzmann, Ralf Burgert, and Hansgeorg Schnockel
Abstract not available. [J. Chem. Phys. 131, 199902 (2009)] published Thu Nov 19, 2009.
Kinetics and morphology of cluster growth in a model of short-range attractive colloids
Siddique J. Khan, C. M. Sorensen, and A. Chakrabarti
We present results from detailed three-dimensional Brownian dynamics simulations of the self-assembly process in quenched short-range attractive colloids. Clusters obtained in the simulations range from dense faceted crystals to fractal aggregates which show ramified morphology on large length scale ... [J. Chem. Phys. 131, 194908 (2009)] published Thu Nov 19, 2009.
Reactions of simple aromatic heterocycles with niobium cluster ions (n<=30)
Britta Pfeffer, Stephanie Jaberg, and Gereon Niedner-Schatteburg
Prior work on benzene activation by size selected niobium cluster cations and anions of up to 30 atoms is extended systematically through studying aromatic poly- and heterocyclic molecules such as naphthalene, pyridine, thiophene, pyrrole, furan, and benzofuran. Naphthalene is found to act much like ... [J. Chem. Phys. 131, 194305 (2009)] published Thu Nov 19, 2009.
Electronic structure of substitutional Mn in epitaxial InMnSb film
N. D. Parashar, D. J. Keavney, and B. W. Wessels
The magnetic and electronic structure of Mn in InMnSb ferromagnetic semiconductor thin film was studied by x-ray absorption spectroscopy and x-ray magnetic circular dichroism. Comparison with atomic multiplet calculations suggests that manganese substitutes on sites with tetrahedral symmetry. Strong ... [Appl. Phys. Lett. 95, 201905 (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.
Emergence of complex behavior in gelling systems starting from simple behavior of single clusters
A. Fierro, T. Abete, and A. Coniglio
A theoretical and numerically study of dynamical properties in the sol-gel transition is presented. In particular, the complex phenomenology observed experimentally and numerically in gelling systems is reproduced in the framework of percolation theory, under simple assumptions on the relaxation of ... [J. Chem. Phys. 131, 194906 (2009)] published Wed Nov 18, 2009.
Unimolecular decomposition of tetrazine-N-oxide based high nitrogen content energetic materials from excited electronic states
A. Bhattacharya, Y. Q. Guo, and E. R. Bernstein
Unimolecular excited electronic state decomposition of novel high nitrogen content energetic molecules, such as 3,3-azobis(6-amino-1,2,4,5-tetrazine)-mixed N-oxides (DAATO), 3-amino-6-chloro-1,2,4,5-tetrazine-2,4-dioxide (ACTO), and 3,6-diamino-1,2,4,5-tetrazine-1,4-dioxde (DATO), is investigated. A ... [J. Chem. Phys. 131, 194304 (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.
Highly mismatched crystalline and amorphous GaNAs alloys in the whole composition range
K. M. Yu, S. V. Novikov, R. Broesler, I. N. Demchenko, J. D. Denlinger et al.
Alloying is a commonly accepted method to tailor properties of semiconductor materials for specific applications. Only a limited number of semiconductor alloys can be easily synthesized in the full composition range. Such alloys are, in general, formed of component elements that are well matched in ... [J. Appl. Phys. 106, 103709 (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.
Experimental demonstration of a nonmagnetic metamaterial cloak at microwave frequencies
Boubacar Kante, Dylan Germain, and Andre de Lustrac
Metamaterials have paved the way to unprecedented control of the electromagnetic field. The conjunction with space coordinate transformation has led to a relativity inspired approach for the control of light propagation. Invisibility cloak is the most fascinating proposed device. However, the realiz ... [Phys. Rev. B 80, 201104 (2009)] published Tue Nov 17, 2009.
Defect-induced optical absorption in the visible range in ZnO nanowires
R. Michael Sheetz, Inna Ponomareva, Ernst Richter, Antonis N. Andriotis, and Madhu Menon
The optical properties of ZnO nanowires containing defects are investigated using first-principles density-functional theory incorporating the LDA+U formalism. Calculations include defects in the form of substitutional N, Zn, and O vacancies as well as +1 charged O vacancy. Our calculations reveal t ... [Phys. Rev. B 80, 195314 (2009)] published Tue Nov 17, 2009.
Dynamical regimes of a paramagnetic particle circulating a magnetic bubble domain
Pietro Tierno, Tom H. Johansen, and Francesc Sagues
We study the dynamics of a single paramagnetic colloidal particle dispersed in water and circulating around a cylindrical magnetic domain (magnetic bubble) when driven by an external rotating magnetic field. We record the particle trajectories and measure its angular displacement by changing the str ... [Phys. Rev. E 80, 052401 (2009)] published Tue Nov 17, 2009.
Triangular tessellation scheme for the adsorption free energy at the liquid-liquid interface: Towards nonconvex patterned colloids
Joost de Graaf, Marjolein Dijkstra, and Rene van Roij
We present a numerical technique, namely, triangular tessellation, to calculate the free energy associated with the adsorption of a colloidal particle at a flat interface. The theory and numerical scheme presented here are sufficiently general to handle nonconvex patchy colloids with arbitrary surfa ... [Phys. Rev. E 80, 051405 (2009)] published Tue Nov 17, 2009.
Arsenic antisite defects in p-GaAs grown by metal-organic chemical-vapor deposition and the EL2 defect
Nazir A. Naz, Umar S. Qurashi, and M. Zafar Iqbal
Epitaxial layers of p-GaAs grown on p-GaAs substrates by low-pressure metal organic chemical vapor deposition have been investigated using deep level transient spectroscopy (DLTS). One dominant peak and other relatively small peak, corresponding to deep levels at E+0.55 eV and E+0.96 (low field ene ... [J. Appl. Phys. 106, 103704 (2009)] published Tue Nov 17, 2009.
Persistent photocurrent and decay studies in CdS nanorods thin films
Gouri Sankar Paul and Pratima Agarwal
Structural and electrical transport properties of thin films of CdS nanorods synthesized by solvothermal process are studied through x-ray diffraction, scanning electron microscopy, transmission electron microscopy, activation energy measurements, and decay of photoconductivity. The films show therm ... [J. Appl. Phys. 106, 103705 (2009)] published Tue Nov 17, 2009.
Dielectric, ferroelectric, and piezoelectric behaviors of AgNbOKNbO solid solution
Desheng Fu, Mitsuru Itoh, and Shin-ya Koshihara
Phase evolution in the (AgK)NbO (AKN) solid solution was investigated by x-ray diffraction, dielectric, and ferroelectric measurements. At room temperature, there are three phase boundaries at x[approximate]0.07, x[approximate]0.20, and x[approximate]0.8. When x
An impedance spectroscopic investigation of the electrical properties of delta-doped diamond structures
Niall Tumilty, Joseph Welch, Richard Lang, Christopher Wort, Richard Balmer et al.
Impedance spectroscopy has been used to investigate the conductivity displayed by diamond doped with boron in an intrinsic-delta-layer-intrinsic multilayer system with differing delta-layer thicknesses. Carrier transport within 5 nm delta-layer structures is complex, being dominated by conduction in ... [J. Appl. Phys. 106, 103707 (2009)] published Tue Nov 17, 2009.
Using Cyclic Voltammetry to Measure Bandgap Modulation of Functionalized Carbon Nanotubes
Matthew L. Gross and Michael A. Hickner
Cyclic voltammograms of gold electrodes laden with carbon nanotubes covalently modified with various electron-withdrawing or donating moieties were measured. Carbon nanotubes modified with electron-donating bromophenyl groups showed a bandgap of 3.0 eV compared to 1.9 eV for unmodified purified tu ... [Electrochem. Solid-State Lett. 13, K5 (2009)] published Tue Nov 17, 2009.
Fractal growth in organic thin films: Experiments and modeling
Gengxin Zhang, Brandon Weeks, Richard Gee, and Amitesh Maiti
Optical microscopy and atomic force microscopy were used to investigate the solidification process of the organic energetic material pentaerythritol tetranitrate thermally deposited on a silicon surface. The metastable films spontaneously undergo dendrite formation where the measured fractal dimensi ... [Appl. Phys. Lett. 95, 204101 (2009)] published Mon Nov 16, 2009.
Exciton polaritons in two-dimensional photonic crystals
D. Bajoni, D. Gerace, M. Galli, J. Bloch, R. Braive et al.
Experimental evidence of strong coupling between excitons confined in a quantum well and the photonic modes of a two-dimensional dielectric lattice is reported. Both resonant scattering and photoluminescence spectra at low temperature show the anticrossing of the polariton branches, fingerprint of s ... [Phys. Rev. B 80, 201308 (2009)] published Mon Nov 16, 2009.
Dynamic rheology of sphere- and rod-based magnetorheological fluids
J. de Vicente, J. P. Segovia-Gutierrez, E. Andablo-Reyes, F. Vereda, and R. Hidalgo-Alvarez
The effect of particle shape in the small amplitude oscillatory shear behavior of magnetorheological (MR) fluids is investigated from zero magnetic field strengths up to 800 kA/m. Two types of MR fluids are studied: the first system is prepared with spherical particles and a second system is prepare ... [J. Chem. Phys. 131, 194902 (2009)] published Mon Nov 16, 2009.
Dielectrophoretic and electrophoretic force analysis of colloidal fullerenes in a nematic liquid-crystal medium
Anoop Kumar Srivastava, Miyoung Kim, Sung Min Kim, Mi-Kyung Kim, Kyu Lee et al.
This research focuses on the electrokinetic motion of fullerenes suspended in liquid crystal host medium, which are investigated in the homogeneously aligned nematic liquid crystal cells driven by in-plane field. We investigated the effect of electrophoretic and dielectrophoretic forces and related ... [Phys. Rev. E 80, 051702 (2009)] published Mon Nov 16, 2009.
Theory of activated-rate processes under shear with application to shear-induced aggregation of colloids
Alessio Zaccone, Hua Wu, Daniele Gentili, and Massimo Morbidelli
Using an approximation scheme within the convective diffusion (two-body Smoluchowski) equation framework, we unveil the shear-driven aggregation mechanism at the origin of structure formation in sheared colloidal systems. The theory, verified against numerics and experiments, explains the induction ... [Phys. Rev. E 80, 051404 (2009)] published Mon Nov 16, 2009.
Near coalescent submicron polycrystalline diamond films deposited on silicon: Hydrogen bonding and thermal enhanced carbide formation
A. Stacey, Sh. Michaelson, J. Orwa, S. Rubanov, S. Prawer et al.
The influence of high temperature annealing up to 1200 degrees C in vacuum on ~100 nm nearly continuous thick diamond films consisting of 3050 nm crystallites, deposited onto silicon substrates is reported. The hydrogen bonding and phase composition of the films were studied with Raman spectroscop ... [J. Appl. Phys. 106, 103503 (2009)] published Mon Nov 16, 2009.
Microstructure and temperature coefficient of resistance of thin cermet resistor films deposited from CrSiCrSiC targets by S-gun magnetron
Valery V. Felmetsger
Technological solutions for producing nanoscale cermet resistor films with sheet resistances above 1000 Omega/[square, open] and low temperature coefficients of resistance (TCR) have been investigated. 240 nm thick cermet films were sputter deposited from CrSiCrSiC targets by a dual cathode dc S-g ... [J. Vac. Sci. Technol. A 28, 33 (2009)] published Mon Nov 16, 2009.
Hyperthermal atomic hydrogen and oxygen etching of vertically oriented graphene sheets
M. Bagge-Hansen, R. A. Outlaw, M. Y. Zhu, H. J. Chen, and D. M. Manos
Carbon nanosheets have previously been shown to be promising high current field emission cathodes for a variety of potential applications. The vertically oriented planar sp carbon nanosheets grown by rf plasma-enhanced chemical vapor deposition terminate with one to seven graphene sheets and grow to ... [J. Vac. Sci. Technol. B 27, 2413 (2009)] published Mon Nov 16, 2009.
Isolated molecular dopants in pentacene observed by scanning tunneling microscopy
Sieu D. Ha and Antoine Kahn
Doping is essential to the control of electronic structure and conductivity of semiconductor materials. Whereas doping of inorganic semiconductors is well established, doping of organic molecular semiconductors is still relatively poorly understood. Using scanning tunneling microscopy, we investigat ... [Phys. Rev. B 80, 195410 (2009)] published Fri Nov 13, 2009.
Silver half-shell arrays with controlled plasmonic response for fluorescence enhancement optimization
Cosmin Farcau and Simion Astilean
Regular arrays of interconnected silver half-shells (HSs) deposited on self-organized polystyrene microspheres are proposed as plasmonic substrates for metal-enhanced fluorescence. An emission enhancement of 28 times was demonstrated for Rose Bengal fluorophore placed at about 1 nm above HSs. The en ... [Appl. Phys. Lett. 95, 193110 (2009)] published Fri Nov 13, 2009.
Practical approach for a rod-connected diamond photonic crystal operating at optical wavelengths
Kanna Aoki
Production of a rod-connected diamond (RCD) photonic crystal structure in a semiconductor material is proposed. Periodic shifting of only one building block can create a complicated three-dimensional network, with a RCD structure exhibiting a full bandgap as wide as 0.20 on a gap/midgap (Deltaomega/ ... [Appl. Phys. Lett. 95, 191910 (2009)] published Fri Nov 13, 2009.
Mapping out the distribution of electronic states in the mobility gap of amorphous zinc tin oxide
Peter T. Erslev, Eric S. Sundholm, Rick E. Presley, David Hong, John F. Wager et al.
Amorphous zinc tin oxide (ZTO) is a wide-band-gap (transparent) semiconductor which exhibits high electron mobilities irrespective of its disordered nature. Transient photocapacitance (TPC), drive level capacitance profiling (DLCP), and modulated photocurrent spectroscopy (MPC) were used to determin ... [Appl. Phys. Lett. 95, 192115 (2009)] published Fri Nov 13, 2009.
Brownian Motion and Temperament of Living Cells. (arXiv:0910.0927v1 [cond-mat.soft])
ePrint arXiv http://arXiv.org/
Strain hardening in bidisperse polymer glasses: Separating the roles of chain orientation and interchain entanglement. (arXiv:0910.1039v1 [cond-mat.soft])
ePrint arXiv http://arXiv.org/
Pressure-energy correlations in liquids. IV. "Isomorphs" in liquid state diagrams. (arXiv:0905.3497v3 [cond-mat.soft] UPDATED)
ePrint arXiv http://arXiv.org/