Giant negative magnetoresistance in semiconductors doped by multiply charged deep impuritiesA giant negative magnetoresistance has been observed in bulk germanium doped with multiply charged deep impurities. Applying a magnetic field the resistance may decrease exponentially at any…S. D. Ganichev, H. Ketterl, W. Prettl et al.·Nov 23, 2000SaveLearn
A physicist's approach to number partitioningThe statistical physics approach to the number partioning problem, a classical NP-hard problem, is both simple and rewarding. Very basic notions and methods from statistical mechanics are enough to…Stephan Mertens·Nov 23, 2000SaveLearn
Dark soliton creation in Bose-Einstein condensatesIt is demonstrated that stable, standing dark solitons can be created in current dilute-gas Bose-Einstein condensate experiments by the proper combination of phase and density engineering. Other…L. D. Carr, J. Brand, S. Burger et al.·Nov 22, 2000SaveLearn
Divergence-free WKB methodA new semiclassical approach to linear (L) and nonlinear (NL) one-dimensional Schrödinger equation (SE) is presented. Unlike the usual WKB solution, our solution does not diverge at the classical…Tadanori Hyouguchi, Satoshi Adachi, Masahito Ueda·Nov 22, 2000SaveLearn
Macroscopic quantum tunneling of the Bose-Einstein condensate trapped in cylindrically symmetric potentialWe investigate the macroscopic quantum tunneling of the attractive Bose-Einstein condensate. Within the effective Lagrangian framework, we find bounce solutions and explicitly calculate the decay…Yukinori Yasui, Takayuki Takaai, Takayoshi Ootsuka·Nov 21, 2000SaveLearn
Cavity assisted quasiparticle damping in a Bose-Einstein condensateWe consider an atomic Bose-Einstein condensate held within an optical cavity and interacting with laser fields. We show how the interaction of the cavity mode with the condensate can cause energy due…S. A. Gardiner, K. M. Gheri, P. Zoller·Nov 20, 2000SaveLearn
On the Best Quadratic Approximation in Feynman's Path Integral Treatment of the PolaronThe best quadratic approximation to the retarded polaron action due to Adamowski et al. and Saitoh is investigated numerically for a wide range of coupling constants. The non-linear variational…R. Rosenfelder, A. W. Schreiber·Nov 20, 2000SaveLearn
Anisotropic exchange interaction of localized conduction-band electrons in semiconductor structuresThe spin-orbit interaction in semiconductors is shown to result in an anisotropic contribution into the exchange Hamiltonian of a pair of localized conduction-band electrons. The anisotropic exchange…K. V. Kavokin·Nov 20, 2000SaveLearn
Equilibrium crystal shapes in the Potts modelThe three-dimensional q-state Potts model, forced into coexistence by fixing the density of one state, is studied for q=2, 3, 4, and 6. As a function of temperature and number of states, we…R. P. Bikker, G. T. Barkema, H. van Beijeren·Nov 20, 2000SaveLearn
Three-loop critical exponents, amplitude functions, and amplitude ratios from variational perturbation theoryWe use variational perturbation theory to calculate various universal amplitude ratios above and below Tc in minimally subtracted phi4-theory with N components in three dimensions. In order to best…H. Kleinert, B. Van den Bossche·Nov 20, 2000SaveLearn
Spin correlations in the two-leg antiferromagnetic ladder in a magnetic fieldWe study the ground-state spin correlations in the gapless incommensurate regime of a S=1/2 XXZ chain and a two-leg antiferromagnetic ladder under a magnetic field, in which the gapless excitations…T. Hikihara, A. Furusaki·Nov 20, 2000SaveLearn
New type of antiferromagnetic state in stacked nanographiteNanographite systems, where graphene sheets of the orders of the nanometer size are stacked, show novel magnetic properties, such as, spin-glass like behaviors and the change of ESR line widths in…Kikuo Harigaya·Nov 20, 2000SaveLearn
Low-lying excitations of a trapped rotating Bose-Einstein condensateWe investigate the low-lying excitations of a weakly-interacting, harmonically-trapped Bose-Einstein condensed gas under rotation, in the limit where the angular mometum L of the system is much…G. M. Kavoulakis, B. Mottelson, S. M. Reimann·Nov 17, 2000SaveLearn
Physical perspectives on the global optimization of atomic clustersIn this chapter the physical aspects of the global optimization of the geometry of atomic clusters are elucidated. In particular, I examine the structural principles that determine the nature of the…Jonathan Doye·Nov 17, 2000SaveLearn
Sympathetic cooling of bosonic and fermionic Lithium gases towards quantum degeneracySympathetic cooling of two atomic isotopes is experimentally investigated. Using forced evaporation of a bosonic 7Li gas in a magnetic trap, a sample of 3 105 6Li fermions has been sympathetically…F. Schreck, G. Ferrari, K. L. Corwin et al.·Nov 16, 2000SaveLearn
A Dynamical Thermostat Approach To Financial Asset Price DynamicsA dynamical price formation model for financial assets is presented. It aims to capture the essence of speculative trading where mispricings of assets are used to make profits. It is shown that…Stefan Thurner·Nov 16, 2000SaveLearn
Fluctuation Pressure of a Stack of MembranesWe calculate the universal pressure constants of a stack of N membranes between walls by strong-coupling theory. The results are in very good agreement with values from Monte-Carlo simulations.Michael Bachmann, Hagen Kleinert, Axel Pelster·Nov 16, 2000SaveLearn
Cooperative Electromagnetic EffectsCollective phenomena in strongly nonequilibrium systems interacting with electromagnetic field are considered. Such systems are described by complicated nonlinear differential or integro-differential…V. I. Yukalov, E. P. Yukalova·Nov 16, 2000SaveLearn
Interacting random Dirac fermions in superconducting cupratesWe study the effects of quasiparticle interactions on disorder-induced localization of Dirac-like nodal excitations in superconducting high-Tc cuprates. As suggested by the experimental ARPES and…D. V. Khveshchenko, A. G. Yashenkin, I. V. Gornyi·Nov 14, 2000SaveLearn
Electron-hole correlations in semiconductor quantum dots with tight-binding wave functionsThe electron-hole states of semiconductor quantum dots are investigated within the framework of empirical tight-binding descriptions for Si, as an example of an indirect gap material, and InAs and…Seungwon Lee, Lars Jonsson, John W. Wilkins et al.·Nov 14, 2000SaveLearn
Nature of traps responsible for failure of MOS devicesA failure of chips in a huge amount of modern electronic devices is connected as a rule with the undesirable capturing of charge (electrons and holes) by traps in a thin insulating film of silicon…V. A. Gritsenko, P. M. Lenahan, Yu. N. Morokov et al.·Nov 14, 2000SaveLearn
Force chain splitting in granular materials: a mechanism for large scale pseudo-elastic behaviourWe investigate both numerically and analytically the effect of strong disorder on the large scale properties of the hyperbolic equations for stresses proposed in bcc,wcc. The physical…J. -P. Bouchaud, P. Claudin, D. Levine et al.·Nov 13, 2000SaveLearn
Legendre's Relation and the Quantum Equivalence osp(4|4)(1) = osp(2|2)(-2) + su(2)(0)Using explicit results for the four-point correlation functions of the Wess-Zumino-Novikov-Witten (WZNW) model we discuss the conformal embedding osp(4|4)(1) = osp(2|2)(-2) + su(2)(0). This…M. J. Bhaseen·Nov 13, 2000SaveLearn
Comment on: "Phenomenological model of Dynamic Nonlinear Response in Relaxor FerroelectricsIn a recent paper (A.E. Glazounov and A.K. Tagantsev, Phys.Rev. Lett. 85, 2192 (2000)) it has been proposed a phenomenological model of the dynamic non-linear response in relaxor ferroelectrics based…B. E. Vugmeister, H. Rabitz·Nov 12, 2000SaveLearn
From Completely Positive Maps to the Quantum Markovian Semigroup Master EquationA central problem in the theory of the dynamics of open quantum systems is the derivation of a rigorous and computationally tractable master equation for the reduced system density matrix. Most…Daniel A. Lidar, Zsolt Bihary, K. Birgitta Whaley·Nov 11, 2000SaveLearn