An Impurity Driven Phase Transition in the Antiferromagnetic Spin-1 ChainUsing an asymptotically exact real space renormalization procedure, we find that the Heisenberg antiferromagnetic spin-1 chain undergoes an impurity driven second order phase transition from the…R. A. Hyman, Kun Yang·Aug 7, 1996SaveLearn
Step-induced unusual magnetic properties of ultrathin Co/Cu films: ab initio studyWe have performed ab initio studies to elucidate the unusual magnetic behavior recently observed in epitaxial Co films upon absorption of submonolayers of Cu and other materials. We find that a…A. V. Smirnov, A. M. Bratkovsky·Aug 7, 1996SaveLearn
Exchange coupling and magnetization profiles of binary and ternary magnetic multilayersWithin a spin-polarized LMTO approach in the Atomic-Sphere approximation we calculate ab initio the magnetic properties of various binary and ternary multilayers composed of Fe, Co, Ni, Cr, V and Cu.…F. Süss, U. Krey, S. Krompiewski·Aug 7, 1996SaveLearn
Power-law correlated phase in random-field XY models and randomly pinned charge-density wavesMonte Carlo simulations have been used to study the Z6 ferromagnet in a random field on simple cubic lattices, which is a simple model for randomly pinned charge-density waves. The random field is…Ronald Fisch·Aug 7, 1996SaveLearn
Dynamics of the 1D Heisenberg model and optical absorption of spinons in cuprate antiferromagnetic chainsWe use numerical and analytical results to construct a simple ansatz for the energy dynamical correlation function of the 1D antiferromagnetic Heisenberg model. This is applied to compute the phonon…J. Lorenzana, R. Eder·Aug 7, 1996SaveLearn
Friction Drag on a Particle Moving in a Nematic Liquid CrystalThe flow of a liquid crystal around a particle does not only depend on its shape and the viscosity coefficients but also on the direction of the molecules. We studied the resulting drag force on a…R. W. Ruhwandl, E. M. Terentjev·Aug 7, 1996SaveLearn
The Pinning Paths of an Elastic InterfaceWe introduce a model describing the paths that pin an elastic interface moving in a disordered medium. We find that the scaling properties of these ``elastic pinning paths'' (EPP) are…Hernan A. Makse, Sergey Buldyrev, Heiko Leschhorn et al.·Aug 7, 1996SaveLearn
Density of states for Bose-Einstein condensation in harmonic oscillator potentialsWe discuss how it is possible to obtain a reliable approximation for the density of states for a system of particles in an anisotropic harmonic oscillator potential. A direct application of the…Klaus Kirsten, David J. Toms·Aug 7, 1996SaveLearn
CPP- Giant Magnetoresistance and Thermo-Electric Power of multilayersOscillations of magnetoresistance and thermo-electric power (TEP) vs. both nonmagnetic spacer as well as ferromagnetic slab thicknesses are studied in the current-perpendicular-to-plane (CPP)…S. Krompiewski, U. Krey·Aug 7, 1996SaveLearn
Quantum Monte Carlo Evidence for d-wave Pairing in the 2D Hubbard Model at a van Hove SingularityWe implement a Quantum Monte Carlo calculation for a repulsive Hubbard model with nearest and next-nearest neighbor hopping interactions on clusters up to 12x12. A parameter region where the Fermi…T. Husslein, I. Morgenstern, D. M. Newns et al.·Aug 7, 1996SaveLearn
Impurity in a Luttinger liquid: a numerical study of the finite size energy spectrum and of the orthogonality catastrophe exponentThe behavior of a single impurity in a one-dimensional Luttinger liquid is numerically investigated by means of the density matrix renormalization group. By analyzing the finite size scaling behavior…Shaojin Qin, Michele Fabrizio, Lu Yu·Aug 6, 1996SaveLearn
Theory of the Breakdown of the Quantum Hall EffectBreakdown of the Quantum Hall Effect at high values of injected current is explained as a consequence of an abrupt formation of a metallic ``river'' percolating from one edge of the sample to…V. Tsemekhman, K. Tsemekhman, C. Wexler et al.·Aug 6, 1996SaveLearn
Ordering temperatures and critical exponents in Ising spin glassesWe propose a numerical criterion which can be used to obtain accurate and reliable values of the ordering temperatures and critical exponents of spin glasses. Using this method we find an value of…L. W. Bernardi, S. Prakash, I. A. Campbell·Aug 6, 1996SaveLearn
The 1/r2 t-J model in a magnetic fieldWe study the one-dimensional supersymmetric t-J model with 1/r2 interaction threaded by magnetic flux. Because of the long range interaction, the effect of this flux leads to a modification of the…J. T. Liu, D. F. Wang·Aug 6, 1996SaveLearn
Dynamics of the Two-Site Hubbard ModelThe dynamical evolution of a two-site Hubbard model is derived in the presence of an uniform external magnetic field for a general initial state. The time evolution of the half-filled (two-particle)…A. T. Costa, M. T. Thomaz·Aug 6, 1996SaveLearn
Noisy Kuramoto-Sivashinsky equation for an erosion modelWe derive the continuum equation for a discrete model for ion sputtering. We follow an approach based on the master equation, and discuss how it can be truncated to a Fokker-Planck equation and…Kent Baekgaard Lauritsen, Rodolfo Cuerno, Hernan A. Makse·Aug 6, 1996SaveLearn
Evolution of photoemission spectral functions in doped transition metal oxidesWe discuss the experimental photoemission and inverse photoemission of early transition metal oxides, in the light of the dynamical mean field theory of correlated electrons which becomes exact in…H. Kajueter, G. Kotliar, D. D. Sarma et al.·Aug 6, 1996SaveLearn
Wavefunction and level statistics of random two dimensional gauge fieldsLevel and wavefunction statistics have been studied for two dimensional clusters of the square lattice in the presence of random magnetic fluxes. Fluxes traversing lattice plaquettes are distributed…J. A. Verges·Aug 6, 1996SaveLearn
Superconductor-normal junction in a strong magnetic field: the double quantum Hall effectPaper withdrawn. A revised version may appear later.Craig Pryor·Aug 5, 1996SaveLearn
Why DNA ?A small collection of general facts related to DNA is presentedH. C. Rosu·Aug 5, 1996SaveLearn
Vertex-corrected tunneling inversion in superconductors: PbThe McMillan-Rowell tunneling inversion program, which extracts the electron-phonon spectral function α2F(Ω) and the Coulomb pseudopotential μ* from experimental tunneling data, is generalized…J. K. Freericks, E. J. Nicol, A. Y. Liu et al.·Aug 5, 1996SaveLearn
Functional Integration in Bose Systems with Hard-Core InteractionA grand canonical ensemble of interacting bosons is considered. The zero temperature phase diagram is evaluated from the mean-field approximation of the functional integral. Three phases are found: a…K. Ziegler·Aug 5, 1996SaveLearn
Skyrmions in the quantum Hall effect at finite Zeeman couplingUsing a self consistent approximation for the spin distribution of Skyrmions in the quantum Hall effect, we obtain an effective action for the Skyrmion coordinates. The energy functional is minimised…A. G. Green, I. I. Kogan, A. M. Tsvelik·Aug 5, 1996SaveLearn
SU(m|n) supersymmetric Calogero-Sutherland model confined in harmonic potentialIn this work, we study a continuous quantum system of a mixture of bosons and fermions with the supersymmetry SU(m|n). The particles are confined in a harmonic well and interact with each other…C. A. Piguet, D. F. Wang, C. Gruber·Aug 5, 1996SaveLearn
Direct Energy Transfer in Systems of Polymerized AcceptorsWe study the direct incoherent energy transfer from an immobile excited donor molecule to acceptor molecules, which are all attached to polymer chains, randomly arranged in a viscous solvent. The…G. Oshanin, J. De Coninck, A. Blumen et al.·Aug 4, 1996SaveLearn