Critical limit and anisotropy in the two-point correlation function of three-dimensional O(N) modelsIn three-dimensional O(N) models, we investigate the low-momentum behavior of the two-point Green's function G(x) in the critical region of the symmetric phase. We consider physical systems whose…Massimo Campostrini, Andrea Pelissetto, Paolo Rossi et al.·Dec 18, 1996SaveLearn
Dynamical Localization: Hydrogen Atoms in Magnetic and Microwave fieldsWe show that dynamical localization for excited hydrogen atoms in magnetic and microwave fields takes place at quite low microwave frequency much lower than the Kepler frequency. The estimates of…Francesco Benvenuto, Giulio Casati, Dima L. Shepelyansky·Dec 17, 1996SaveLearn
New evidence for super-roughening in crystalline surfaces with disordered substrateWe study the behavior of the Binder cumulant related to long distance correlation functions of the discrete Gaussian model of disordered substrate crystalline surfaces. We exhibit numerical evidence…Barbara Coluzzi, Enzo Marinari, Juan J. Ruiz-Lorenzo·Dec 16, 1996SaveLearn
C-axis Raman spectra of a normal plane-chain bilayer cuprate and the pseudogapWe investigate the Raman spectra in the geometry where both incident and scattered photon polarizations are parallel to the z-direction, for a plane-chain bilayer coupled via a…W. C. Wu, J. P. Carbotte·Dec 16, 1996SaveLearn
Resonant Tunneling through Multi-Level and Double Quantum DotsWe study resonant tunneling through quantum-dot systems in the presence of strong Coulomb repulsion and coupling to the metallic leads. Motivated by recent experiments we concentrate on (i) a single…T. Pohjola, J. König, M. M. Salomaa et al.·Dec 16, 1996SaveLearn
A Plaquette Basis for the Study of Heisenberg LaddersWe employ a plaquette basis-generated by coupling the four spins in a 2×2 lattice to a well-defined total angular momentum-for the study of Heisenberg ladders with antiferromagnetic coupling.…J. Piekarewicz, J. R. Shepard·Dec 14, 1996SaveLearn
A complete devil's staircase in the Falicov-Kimball modelWe consider the neutral, one-dimensional Falicov-Kimball model at zero temperature in the limit of a large electron--ion attractive potential, U. By calculating the general n-ion interaction terms to…C. Micheletti, A. B. Harris, J. M. Yeomans·Dec 14, 1996SaveLearn
Quantum localization in rough billiardsWe study the level spacing statistics p(s) and eigenfunction properties in a billiard with a rough boundary. Quantum effects lead to localization of classical diffusion in the angular momentum space…Klaus M. Frahm, Dima L. Shepelyansky·Dec 12, 1996SaveLearn
Magnus and Iordanskii Forces in SuperfluidsThe total transverse force acting on a quantized vortex in a superfluid is a problem that has eluded a complete understanding for more than three decades. In this letter I propose a remarkably simple…C. Wexler·Dec 11, 1996SaveLearn
Symmetries and Fixed Point Stability of Stochastic Differential Equations Modeling Self-Organized CriticalityA stochastic nonlinear partial differential equation is built for two different models exhibiting self-organized criticality, the Bak, Tang, and Wiesenfeld (BTW) sandpile model and the Zhang's…Alvaro Corral, Albert Diaz-Guilera·Dec 11, 1996SaveLearn
Collisional matter-phase damping in Bose-condensed gasCollisional damping of the excitations in a Bose-condensed gas is investigated over the wide range of energies and temperatures. Numerical results for the damping rate are presented and a number of…L. I. Plimak, M. J. Collett, D. F. Walls·Dec 10, 1996SaveLearn
A New Perturbation Theory of Finite-Size Effects Near Critical PointA new perturbation theory is proposed for studying finite-size effects near critical point of the ϕ4 model with a one-component order parameter. The new approach is based on the techniques of…C. B. Yang, X. Cai·Dec 10, 1996SaveLearn
Exact Quantum Monte Carlo Process for the Statistics of Discrete SystemsWe introduce an exact Monte Carlo approach to the statistics of discrete quantum systems which does not rely on the standard fragmentation of the imaginary time, or any small parameter. The method…N. V. Prokof'ev, B. V. Svistunov, I. S. Tupitsyn·Dec 9, 1996SaveLearn
Surface spin-flop phases and bulk discommensurations in antiferromagnetsPhase diagrams as a function of anisotropy D and magnetic field H are obtained for discommensurations and surface states for a model antiferromagnet in which H is parallel to the easy axis. The…C. Micheletti, R. B. Griffiths, J. M. Yeomans·Dec 9, 1996SaveLearn
Aging in Models of Non-linear DiffusionWe show that for a family of problems described by non-linear diffusion equations an exact calculation of the two time correlation function gives C(t,t')=f(t-t')g(t'), t>t',…Daniel A. Stariolo·Dec 9, 1996SaveLearn
On Phase Ordering Behind the Propagating Front of a Second-Order TransitionIn a real system the heating is nonuniform and a second-order phase transition into a broken symmetry phase occurs by propagation of the temperature front. Two parameters, the cooling rate τQ and…T. W. B. Kibble, G. E. Volovik·Dec 9, 1996SaveLearn
Behavior of a frustrated quantum spin chain with bond dimerizationWe clarified behavior of the excitation gap in a frustrated S=1/2 quantum spin chain with bond dimerization by using the numerical diagonalization of finite systems and a variational approach. The…Tota Nakamura, Satoshi Takada·Dec 7, 1996SaveLearn
Precursors, aftershocks, criticality and self-organized criticalityWe present a simple model of earthquakes on a pre-existing hierarchical fault network. The system self-organizes on long time scales in a stationary state with a power law Gutenberg-Richter…Y. Huang, H. Saleur, C. G. Sammis et al.·Dec 7, 1996SaveLearn
Collapses and Revivals of Collective Excitations in Trapped Bose CondensatesWe present a quantum theory of low-lying excitations in a trapped Bose condensate with finite particle numbers. We find that even at zero temperature condensate number fluctuations and/or…R. Graham, D. F. Walls, M. J. Collett et al.·Dec 6, 1996SaveLearn
Application of Instantons: Quenching of Macroscopic Quantum Coherence and Macroscopic Fermi-Particle ConfigurationsStarting from the coherent state representation of the evolution operator with the help of the path-integral, we derive a formula for the low-lying levels E = ε0 - 2εcos (s+ξ)π of a…J. -Q. Liang, H. J. W. Mueller-Kirsten, Jian-Ge Zhou·Dec 6, 1996SaveLearn
Effective Vortex Dynamics in Superfluid SystemsAn alternative approach to the derivation of the force on a vortex based in an adiabatic approximation in the action of the superfluid system is developed. Assuming that the vortex motion is…C. Wexler, D. J. Thouless·Dec 6, 1996SaveLearn
Eugene Wigner and Translational SymmetriesAs Einstein's E = mc2 unifies the energy-momentum relation for massive and massless particles, Wigner's little group unifies their internal space-time symmetries. It is pointed out that…Y. S. Kim·Dec 5, 1996SaveLearn
Vortex annihilation in the ordering kinetics of the O(2) modelThe vortex-vortex and vortex-antivortex correlation functions are determined for the two-dimensional O(2) model undergoing phase ordering. We find reasonably good agreement with simulation results…Gene F. Mazenko, Robert A. Wickham·Dec 5, 1996SaveLearn
Correlations in one dimensional quantum impurity problems with an external field or a temperatureWe discuss in more details the theory of low energy excitations in quantum impurity problems with an external field at vanishing temperature, giving further support to results of the previous paper.…F. Lesage, H. Saleur·Dec 4, 1996SaveLearn
Dynamics of Electrons in Graded SemiconductorsI present a theory of electron dynamics in semiconductors with slowly varying composition. I show that the frequency-dependent conductivity, required for the description of transport and optical…Michael R. Geller·Dec 4, 1996SaveLearn