Comparative statistical analysis of bacteria genomes in "word" contextStatistical analysis of bacteria genomes texts has been performed on the basis of 20 complete genomes origin from Genebank. It has been revealed that the word ranked distributions are quite well…Olga V. Kirillova·Oct 17, 2000SaveLearn
Spin-Orbit Coupling in the ab initio Pseudopotential FrameworkWe describe the implementation of total angular momentum dependent pseudopotentials in a plane wave formulation of density functional theory. Our approach thus goes beyond the scalar-relativistic…G. Theurich, N. A. Hill·Oct 17, 2000SaveLearn
Stable Vortex Configurations in a CylinderWe calculate stable arrangements for a single superfluid vortex pinned to the wall of a stationary cylindrical container. We find that, independent of the details of the pinning site, stable vortices…R. J. Zieve, L. A. K. Donev·Oct 17, 2000SaveLearn
Spin waves in ultrathin ferromagnetic overlayersThe influence of a non-magnetic metallic substrate on the spin wave excitations in ultrathin ferromagnetic overlayers is investigated for different crystalline orientations. We show that spin wave…L. H. M. Barbosa, A. T. Costa, J. Mathon et al.·Oct 16, 2000SaveLearn
Transition-metal interactions in aluminum-rich intermetallicsThe extension of the first-principles generalized pseudopotential theory (GPT) to transition-metal (TM) aluminides produces pair and many-body interactions that allow efficient calculations of total…Ibrahim Al-Lehyani, Mike Widom, Yang Wang et al.·Oct 15, 2000SaveLearn
A Statistical Mechanics Approach to the Inherent States of Granular MediaWe consider a Statistical Mechanics approach to granular systems by following the original ideas developed by Edwards. We use the concept of ``inherent states'', defined as the stable…Antonio Coniglio, Mario Nicodemi·Oct 13, 2000SaveLearn
Ab initio calculations of response properties including electron-hole interactionWe discuss the current status of a computational approach which allows to evaluate the dielectric matrix, and hence electronic excitations like optical properties, including local field and excitonic…Valerio Olevano, Stefan Albrecht, Lucia Reining·Oct 13, 2000SaveLearn
Glassy effects in the swelling/collapse dynamics of homogeneous polymersWe investigate, using numerical simulations and analytical arguments, a simple one dimensional model for the swelling or the collapse of a closed polymer chain of size N, representing the dynamical…E. Pitard, J. -P. Bouchaud·Oct 12, 2000SaveLearn
A non-perturbative treatment of the generalized Su-Schreiffer-Heeger Hamiltonian on a dimerStarting from the Hamiltonian for a dimer which includes all the electronic and electron-phonon terms consistent with a non-degenerate orbital, by a sequence of displacement and squeezing…M. Cococcioni, M. Acquarone·Oct 11, 2000SaveLearn
Spatially modulated magnetic structures in thin filmsThe axial next-nearest neighbour Ising (ANNNI) model is studied for thin films of up to L= 10 layers, with a distinct phase diagram for each film thickness. The systematics of the ordered phases,…W. Selke, D. Catrein, M. Pleimling·Oct 10, 2000SaveLearn
Atomic Solitons in Optical LatticesThe experimental demonstration of Bose-Einstein condensation in atomic vapors has rapidly lead to new advances in atom optics. It is now well established that two-body collisions play for matter…S. Potting, P. Meystre, E. M. Wright·Oct 10, 2000SaveLearn
Features of Hopping Integral and Unconventional Orbital Modes for Quantum Skyrmions in Heisenberg FerromagnetWe use the coherent state approximation for the skyrmion in the isotropic quantum Heisenberg ferromagnet to obtain analytical expression for skyrmion hopping integral as a function of distance. It…R. A. Istomin, A. S. Moskvin·Oct 10, 2000SaveLearn
Adiabatic Inversion in the SQUID, Macroscopic Coherence and DecoherenceA procedure for demonstrating quantum coherence and measuring decoherence times between different fluxoid states of a SQUID by using ``adiabatic inversion'' is discussed. One fluxoid state is…P. Silvestrini, L. Stodolsky·Oct 9, 2000SaveLearn
Local magnetic properties of periodic nonuniform spin-1/2 XX chainsUsing the Jordan-Wigner fermionization, Green function approach and continued fractions we examine rigorously the local magnetizations and the local static susceptibilities of the spin-1/2 XX chain…Oleg Derzhko, Johannes Richter, Oles' Zaburannyi·Oct 7, 2000SaveLearn
Spin-Peierls instability in a quantum spin chain with Dzyaloshinskii-Moriya interactionWe analysed the ground state energy of some dimerized spin-1/2 transverse XX and Heisenberg chains with Dzyaloshinskii-Moriya (DM) interaction to study the influence of the latter interaction on the…O. Derzhko, J. Richter, O. Zaburannyi·Oct 7, 2000SaveLearn
Quasiparticle kinetic equation in a trapped Bose gas at low temperaturesRecently the authors used the Kadanoff-Baym non-equilibrium Green's function formalism to derive kinetic equation for the non-condensate atoms, in conjunction with a consistent generalization of…M. Imamovic-Tomasovic, A. Griffin·Oct 6, 2000SaveLearn
On the Ginzburg-Landau Free Energy of Charge Density Waves with a Three-Dimensional OrderThe effective free energy of a charge density wave (CDW) with a three-dimensional order is derived from a microscopic model (Frölich model) based on the path integral method. Electron hoping and…Masahiko Hayashi, Hideo Yoshioka·Oct 6, 2000SaveLearn
Acoustic wave propagation in an one-dimensional layered systemPropagation of acoustic waves in an one-dimensional water duct containing many air filled blocks is studied by the transfer matrix formalism. Energy distribution and interface vibration of the air…Pi-Gang Luan, Zhen Ye·Oct 5, 2000SaveLearn
Stability of Repulsive Bose-Einstein Condensates in a Periodic PotentialThe cubic nonlinear Schrödinger equation with repulsive nonlinearity and an elliptic function potential models a quasi-one-dimensional repulsive dilute gas Bose-Einstein condensate trapped in a…J. C. Bronski, L. D. Carr, B. Deconinck et al.·Oct 5, 2000SaveLearn
Screening Breakdown on the Route toward the Metal-Insulator Transition in Modulation Doped Si/SiGe Quantum WellsExploiting the spin resonance of two-dimensional (2D) electrons in SiGe/Si quantum wells we determine the carrier-density-dependence of the magnetic susceptibility. Assuming weak interaction we…Z. Wilamowski, N. Sandersfeld, W. Jantsch et al.·Oct 5, 2000SaveLearn
Specific heat of (Y,Lu)Ni2B2C in the mixed stateThe temperature and magnetic field dependences of the electronic specific heat in the superconducting mixed state as well as the upper critical field have been measured on a (Y,Lu)Ni2B2C series to…D. Lipp, M. Schneider, A. Gladun et al.·Oct 4, 2000SaveLearn
Direct Minimization Generating Electronic States with Proper Occupation NumbersWe carry out the direct minimization of the energy functional proposed by Mauri, Galli and Car to derive the correct self-consistent ground state with fractional occupation numbers for a system…Kikuji Hirose, Tomoya Ono·Oct 4, 2000SaveLearn
Effective Dimension Transition of the Dynamics of Granular Materials in the PipePhase transition of strongly excited granular materials in 2D pipe is investigated numerically. By changing the ratio between width of the pipe and the height of the granular bed, we observe the…Akinori Awazu·Oct 4, 2000SaveLearn
Large Stock Market Price Drawdowns Are OutliersDrawdowns are essential aspects of risk assessment in investment management. They offer a more natural measure of real market risks than the variance or other cumulants of daily (or some other fixed…Anders Johansen, Didier Sornette·Oct 3, 2000SaveLearn
Magnetization processes in quantum spin chains with regularly alternating intersite interactionsWe consider the dependence magnetization vs. field at zero temperature for the spin-1/2 chains in which the intersite interactions regularly vary from site to site with a period p. In the limiting…Oleg Derzhko·Oct 3, 2000SaveLearn