Even-odd correlations in capacitance fluctuations of quantum dotsWe investigate effects of short range interactions on the addition spectra of quantum dots using a disordered Hubbard model. A correlation function (q) is defined on the inverse compressibility…O. Prus, A. Auerbach, Y. Aloni et al.·Jul 8, 1996SaveLearn
Synchronization of Integrate and Fire oscillators with global couplingIn this article we study the behavior of globally coupled assemblies of a large number of Integrate and Fire oscillators with excitatory pulse-like interactions. On some simple models we show that…Samuele Bottani·Jul 8, 1996SaveLearn
Scaling Properties of Localization Length in 1D Paired Correlated Binary Alloys of Finite SizeWe study scaling properties of the localized eigenstates of the random dimer model in which pairs of local site energies are assigned at random in a one dimensional disordered tight-binding model. We…F. M. Izrailev, T. Kottos, G. P. Tsironis·Jul 8, 1996SaveLearn
Theory of Exciton Migration and Field-Induced Dissociation in Conjugated PolymersThe interplay of migration, recombination, and dissociation of excitons in disordered media is studied theoretically in the low temperature regime. An exact expression for the photoluminescence…M. C. J. M. Vissenberg, M. J. M. de Jong·Jul 8, 1996SaveLearn
Ground states with cluster structures in a frustrated Heisenberg chainWe examine the ground state of a Heisenberg model with arbitrary spin S on a one-dimensional lattice composed of diamond-shaped units. A unit includes two types of antiferromagnetic exchange…K. Takano, K. Kubo, H. Sakamoto·Jul 8, 1996SaveLearn
Dynamic Conductance in Quantum Hall SystemsIn the framework of the edge-channel picture and the scattering approach to conduction, we discuss the low frequency admittance of quantized Hall samples up to second order in frequency. The…M. Buttiker, T. Christen·Jul 8, 1996SaveLearn
Phase Diagram and Pairing Symmetry of the Two-Dimensional t-J Model by a Variation TheoryTwo-dimensional t-J model is studied by a variational Monte Carlo method, using Gutzwiller-Jastrow-type wave functions. Various kinds of superconducting pairing symmetries are compared in order to…Hisatoshi Yokoyama, Masao Ogata·Jul 8, 1996SaveLearn
Multiple light scattering in nematic liquid crystalsWe present a rigorous treatment of the diffusion approximation for multiple light scattering in anisotropic random media, and apply it to director fluctuations in a nematic liquid crystal. For a…Holger Stark, Tom C. Lubensky·Jul 7, 1996SaveLearn
Fractals, Multifractals and the Science of ComplexityWe discuss the formation of stochastic fractals and multifractals using the kinetic equation of fragmentation approach. We also discuss the potential application of this sequential breaking and…M. K. Hassan·Jul 7, 1996SaveLearn
Bose-Einstein condensation of atomic gases in a general harmonic oscillatorWe present an analysis of Bose-Einstein condensation for a system of non-interacting spin-0 particles in a harmonic oscillator confining potential trap. We discuss why a confined system of particles…Klaus Kirsten, David J. Toms·Jul 7, 1996SaveLearn
Generalized gradient approximations to density functional theory: comparison with exact resultsIn order to assess the accuracy of commonly used approximate exchange-correlation density functionals, we present a comparison of accurate exchange and correlation potentials, exchange energy…Claudia Filippi, Xavier Gonze, C. J. Umrigar·Jul 7, 1996SaveLearn
Separation of the Exchange-Correlation Potential into Exchange plus Correlation: an Optimized Effective Potential ApproachMost approximate exchange-correlation functionals used within density functional theory are constructed as the sum of two distinct contributions for exchange and correlation. Separating the exchange…Claudia Filippi, C. J. Umrigar, Xavier Gonze·Jul 7, 1996SaveLearn
Quantum critical effects in mean-field glassy systemsWe consider the effects of quantum fluctuations in mean-field quantum spin-glass models with pairwise interactions. We examine the nature of the quantum glass transition at zero temperature in a…Felix Ritort·Jul 6, 1996SaveLearn
Mean-field limit of the random flux modelThe problem of non--interacting electrons on a square lattice subject to a random magnetic flux is mapped onto a one--dimensional model with infinitely many orbitals per site. Linking each orbital…B. Kramer, D. Belitz, M. Batsch·Jul 6, 1996SaveLearn
Statistics of Mesoscopic Fluctuations of Quantum CapacitanceThe Thouless formula \(G = (e2/h)(Ec/Δ)\) for the two-probe dc conductance G of a d-dimensional mesoscopic cube is re-analysed to relate its quantum capacitance CQ to the reciprocal of the…N. Kumar, A. M. Jayannavar·Jul 5, 1996SaveLearn
Exact results of a hard-core interacting system with a single impurityThe quantum-mechanical problem of a many-particle system with a single impurity in one-dimension, interacting by a delta-function, is solved. The wave-function for a bosonic system and the related…You-Quan Li, Zhong-Shui Ma·Jul 5, 1996SaveLearn
Training a perceptron by a bit sequence: Storage capacityA perceptron is trained by a random bit sequence. In comparison to the corresponding classification problem, the storage capacity decreases to alphac=1.70 0.02 due to correlations between input…M. Schroeder, W. Kinzel, I. Kanter·Jul 5, 1996SaveLearn
Influence of hydrodynamic interactions on the ballistic deposition of colloidal particles on solid surfacesThe ballistic deposition of particles by taking hydrodynamic interactions (HI) into account has been studied by means of computer simulations. The radial distribution function of the assembly of…I. Pagonabarraga, P. Wojtaszczyk, J. M. Rubi et al.·Jul 5, 1996SaveLearn
Droplet Fluctuations in the Morphology and Kinetics of MartensitesWe derive a coarse grained, free-energy functional which describes droplet configurations arising on nucleation of a product crystal within a parent. This involves a new `slow' vacancy mode that…Madan Rao, Surajit Sengupta·Jul 5, 1996SaveLearn
Effects of spin fluctuations in the t-J modelRecent experiments on the Fermi surface and the electronic structure of the cuprate-supercondutors showed the importance of short range antiferromagnetic correlations for the physics in these…T. Obermeier, T. Pruschke, J. Keller·Jul 5, 1996SaveLearn
Superconductor-proximity effect in chaotic and integrable billiardsWe explore the effects of the proximity to a superconductor on the level density of a billiard for the two extreme cases that the classical motion in the billiard is chaotic or integrable. In zero…J. A. Melsen, P. W. Brouwer, K. M. Frahm et al.·Jul 5, 1996SaveLearn
Towards a Statistical Theory of Finite Systems and Compound States: Random Two-Body Interaction ApproachThe model of Fermi particles with random two-body interaction is investigated. This model allows to study the origin and accuracy of statistical laws in few-body systems, the role of interaction and…V. V. Flambaum, F. M. Izrailev, G. Casati·Jul 5, 1996SaveLearn
Dynamical Magnetic Susceptibility for the t-J ModelWe present results for the dynamical\/ magnetic susceptibility of the t-J model, calculated with the dynamical mean field theory. For J=0 we find enhanced ferromagnetic correlations but…Th. Pruschke, Th. Obermeier, J. Keller·Jul 5, 1996SaveLearn
Surface Free Energies, Interfacial Tensions and Correlation Lengths of the ABF ModelsThe surface free energies, interfacial tensions and correlation lengths of the Andrews-Baxter-Forrester models in regimes III and IV are calculated with fixed boundary conditions. The interfacial…David L. O'Brien, Paul A. Pearce·Jul 5, 1996SaveLearn
The Quantized Hall InsulatorWe model the insulator neighboring the 1/k quantum Hall phase by a random network of puddles of filling fraction 1/k. The puddles are coupled by weak tunnel barriers. Using Kirchoff's laws we…Efrat Shimshoni, Assa Auerbach·Jul 4, 1996SaveLearn