Volume 1
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Magnetic modulation in mechanical alloyed Cr1.4Fe0.6O3 oxide
RN Bhowmik, M Nrisimha Murty, E Sekhar Srinadhu PMC Physics B 2008, 1:20 (29 December 2008)
Cr1.4Fe0.6O3 compound is synthesized through mechanical alloying of Cr2O3 and Fe2O3 powders and subsequent thermal annealing. The XRD spectrum, SEM picture and microanalysis of EDAX spectrum are used to understand the structural evolution in the alloyed compound. -
Upper critical field H
c 2 in Bechgaard salts (TMTSF)2PF6Ana D Folgueras, Kazumi Maki PMC Physics B 2008, 1:19 (9 December 2008)
The symmetry of the superconductivity in Bechgaard salts is still unknown, though the triplet pairing has been established by Hc2 and NMR for (TMTSF)2PF6. Here we start with a low energy effective Hamiltonian and study the temperature dependence of the corresponding Hc2(T)'s. -
Mg spin affects adenosinetriphosphate activity
Alexander A Tulub PMC Physics B 2008, 1:18 (4 December 2008)
Schlegel-Frisch ab initio molecular dynamics (ADMP) (DFT:B3LYP), T = 310 K, are used to study complexation between adenosinetriphosphate (ATP), ATP subsystem, and magnesium cofactor [Mg(H2O)6]2+, Mg subsystem, in a water pool modeled with 78 water molecules. The computations prove that ATP cleavage is governed by the electron spin of Mg. -
Effect of biased noise fluctuations on the output radiation of coherent beat laser
Sintayehu Tesfa PMC Physics B 2008, 1:17 (1 December 2008)
The effects of biased noise fluctuations on the degree of squeezing and intensity of radiation both inside and outside the cavity of a one-photon coherent beat laser are presented. -
Evolution of structure of SiO2 nanoparticles upon cooling from the melt
Nguyen Xuan Huynh, Vo Van Hoang, Hoang Zung PMC Physics B 2008, 1:16 (30 October 2008)
Evolution of structure of spherical SiO2 nanoparticles upon cooling from the melt has been investigated via Molecular Dynamics simulations under non-periodic boundary conditions. Our results show significant temperature dependence of structure of nanoparticles, and we discuss the temperature dependence of the concentration of structural defects. -
Effect of the applied magnetic field on formation of complex polyaniline films
Oleg P Dimitriev, Petro M Lytvyn, Alla P Dimitriyeva, Ostap M Getsko PMC Physics B 2008, 1:15 (21 October 2008)
It has been found that an applied magnetic field affects the interaction of polyaniline chains with paramagnetic metal ion impurities, and induces formation of magnetically ordered regions in contrast to the reference film of the same composition but prepared under ambient conditions. Correlations are found between the distribution of magnetically ordered regions and peculiarities of the surface relief of a film. -
D Schmeltzer, Hsuan Chang PMC Physics B 2008, 1:14 (21 October 2008)
We investigate the effect of a microwave field on a confined two dimensional electron gas containing an insulating region comparable to the Fermi wavelength. A Bosonized formulation of the two dimensional gas in the presence of insulating regions allows us to compute the rectified current. The proposed theory may explain experimental results recently reported by J. Zhang et al. -
Ab-initio calculations of spin tunneling through an indirect barrier
Athanasios N Chantis, Titus Sandu, Jialei L Xu PMC Physics B 2008, 1:13 (6 June 2008)
We use a fully relativistic layer Green’s functions approach to investigate spin-dependent tunneling through a symmetric indirect band gap barrier like GaAs/AlAs/GaAs heterostructure. Our calculations show clearly that the appearance of energy windows with significant spin polarization depends mostly on the location of transmission resonances and their corresponding zeros and not on the magnitude of the spin splitting in the barrier. -
Ali Reshak, S Auluck PMC Physics B 2008, 1:12 (19 May 2008)
We present results for band structure, density of states, and the imaginary part of the frequency-dependent linear and nonlinear optical susceptibilities for CuInX2 (X=S, Se, Te) chalcopyrite-structure single crystals. We find that these crystals are semiconductors with direct band gaps, and have calculated their birefringence and frequency-dependent complex second-order non-linear optical susceptibilities. -
Iskandar Chaabane, Faouzi Hlel, Kamel Guidara PMC Physics B 2008, 1:11 (8 April 2008)
We report on the synthesis, crystal structure and infra-red, Raman and NMR spectra of 2, 4, 4- trimethyl-4, 5- dihydro-3H-benzo[b] [1, 4] diazepin-1-ium tetrachlorocadmate, [C12H17N2]2CdCl4 and benzene-1,2-diaminium decachlorotricadmate(II) [C6H10N2]2Cd3Cl10. -
Fast and accurate simulations of transmission-line metamaterials using transmission-matrix method
Hui Ma, Tie Cui, Jessie Chin, Qiang Cheng PMC Physics B 2008, 1:10 (8 April 2008)
Recently, two-dimensional periodically L and C loaded transmission-line (TL) networks have been applied to represent metamaterials. We propose an efficient transmission-matrix method (TMM) to simulate and analyze the TL-network metamaterials, which provides nearly the same simulation results as Agilent's Advanced Design System whilst greatly reducing model-processing and simulation times. -
Zone center phonons of the orthorhombic RMnO3 (R = Pr, Eu, Tb, Dy, Ho) perovskites
HC Gupta, Upendra Tripathi PMC Physics B 2008, 1:9 (17 March 2008)
A short range force constant model (SRFCM) has been applied for the first time to investigate the phonons in RMnO3 (R = Pr, Eu, Tb, Dy, Ho) perovskites in their orthorhombic phase. -
Ali H Reshak, S Auluck, A Majchrowski, IV Kityk PMC Physics B 2008, 1:8 (17 March 2008)
Experimental measurements of the second order susceptibilities for second harmonic generation are reported for YAl3(BO3)4 (YAB) single crystals. First principles calculations within a framework of the fullpotential linear augmented plane wave (FP-LAPW) method show a large anisotropy of the linear and nonlinear optical susceptibilities. -
G Venkataiah, YK Lakshmi, PV Reddy PMC Physics B 2008, 1:7 (12 March 2008)
A systematic investigation of La0.67Ca0.33MnO3 manganites looks at the influence of varying crystallite size (nano meter range) on electrical resistivity, magnetic susceptibility and thermoelectric power. The metal-insulator transition temperatures are found to increase with increasing sintering temperatures, while the magnetic transition temperatures decrease. -
Evidence of phonon-assisted tunnelling in electrical conduction through DNA molecules
Povilas Pipinys, Antanas Kiveris PMC Physics B 2008, 1:6 (19 February 2008)
We propose a phonon-assisted tunnelling model for explanation of some of the peculiarities of the dependence of the conductivity of DNA molecules on temperature. -
Sergey A Reshetnyak, Tat'yana A Homenko PMC Physics B 2008, 1:5 (14 February 2008)
The reflection coefficient of bulk spin waves from multilayer ferromagnetic structure is calculated with a non-ideal coupling between layers. The proposed model gives the opportunity to consider the quality of interfaces when studying the reflection processes of spin waves in multilayer structures. -
Microwave dielectric spectroscopy of pure and mixed aromatic ester solvents
Santiago Aparicio, Rafael Alcalde PMC Physics B 2008, 1:4 (12 February 2008)
The structure and dynamics of pure and mixed liquid aromatic esters is studied through microwave dielectric relaxation spectroscopy. Data are analyzed in terms of the proposed different species present in the fluids and their evolution with composition for mixtures, and with temperature and chain length for pure esters. -
Electron cooling by carbon monoxide in the atmospheres of Mars and Venus
Laurence Campbell, Michael J Brunger PMC Physics B 2008, 1:3 (4 February 2008)
Electron cooling, in which free electrons lose energy to vibrational excitation of gases, has been identified as a significant process in the atmospheres of Mars and Venus for electron impact on CO2. In this paper electron cooling rates for CO are calculated and compared with existing rates for CO2. -
JC Knott, DC Pond, RA Lewis PMC Physics B 2008, 1:2 (4 February 2008)
Certain perovskites exhibit colossal magnetoresistance, but here the authors report simultaneous observation of metal-insulator transition and electroresistance in the lanthanum/calcium manganites. This was accomplished by measuring voltage-current curves over a wide temperature range (10-300 K), to build up an experimental voltage surface over current-temperature axes. -
Stephen Buckman, Peter Hatton PMC Physics B 2008, 1:1 (4 February 2008)