Uniform electron gas from two-particle wavefunctionsAn approximation for the unknown two-electron wavefunctions (geminals) of the interacting uniform electron gas is found, starting from the effective screened Coulomb potential proposed by Overhauser…Paola Gori-Giorgi·Nov 8, 2001SaveLearn
Spin Coherent-State Path Integrals and the Instanton CalculusWe use an instanton approximation to the continuous-time spin coherent-state path integral to obtain the tunnel splitting of classically degenerate ground states. We show that provided the…Anupam Garg, Evgueny Kochetov, Kee-Su Park et al.·Nov 8, 2001SaveLearn
Interlayer Exchange Coupling in M/N/M MultilayerThe interlayer exchange coupling (IEC) of two local moment ferromagnetic layers separated by a non-magnetic spacer layer (M/N/M multilayer) is studied using the modified RKKY method along with the…S. Mathi Jaya, M. C. Valsakumar, W. Nolting·Nov 8, 2001SaveLearn
Discrete Breathers in Anisotropic Ferromagnetic Spin ChainsWe prove the existence of discrete breathers (time-periodic, spatially localized solutions) in weakly coupled ferromagnetic spin chains with easy-axis anisotropy. Using numerical methods we then…J. M. Speight, P. M. Sutcliffe·Nov 6, 2001SaveLearn
Coherent Tunneling of Atoms from Bose-condensed Gases at Finite TemperaturesTunneling of atoms between two trapped Bose-condensed gases at finite temperatures is explored using a many-body linear response tunneling formalism similar to that used in superconductors. To lowest…David L. Luxat, Allan Griffin·Nov 2, 2001SaveLearn
Evidence for Slow Velocity Relaxation in Front Propagation in Rayleigh-Bénard ConvectionRecent theoretical work has shown that so-called pulled fronts propagating into an unstable state always converge very slowly to their asymptotic speed and shape. In the the light of these…Julien Kockelkoren, Cornelis Storm, Wim van Saarloos·Nov 2, 2001SaveLearn
Linewidth of single photon transitions in Mn12-acetateWe use time-domain terahertz spectroscopy to measure the position and linewidth of single photon transitions in Mn12-acetate. This linewidth is compared to the linewidth measured in tunneling…Beth Parks, Joseph Loomis, Evan Rumberger et al.·Oct 31, 2001SaveLearn
Monte Carlo simulation of electromigration phenomena in metallic linesThe electromigration (EM) of metallic lines is studied in terms of competition between two percolative processes taking place in a random resistor network. The effects associated with the transport…C. Pennetta, L. Reggiani, E. Alfinito·Oct 31, 2001SaveLearn
Dynamics of Quantum Phase Transition in an Array of Josephson JunctionsWe study the dynamics of the Mott insulator-superfluid quantum phase transition in a periodic 1D array of Josephson junctions. We show that crossing the critical point diabatically i.e. at a finite…J. Dziarmaga, A. Smerzi, W. H. Zurek et al.·Oct 30, 2001SaveLearn
Thermodynamics "beyond" local equilibriumNonequilibrium thermodynamics has shown its applicability in a wide variety of different situations pertaining to fields such as physics, chemistry, biology, and engineering. As successful as it is,…J. M. G. Vilar, J. M. Rubi·Oct 30, 2001SaveLearn
Noise suppression by noiseWe have analyzed the interplay between an externally added noise and the intrinsic noise of systems that relax fast towards a stationary state, and found that increasing the intensity of the external…J. M. G. Vilar, J. M. Rubi·Oct 30, 2001SaveLearn
Substrate Interface InteractionsBy utilizing the current transients in scanning tunneling spectroscopy, the local interfacial electronics between multiwalled carbon nanotubes and several supporting substrates has been investigated.…R. Czerw, B. Foley, D. Tekleab et al.·Oct 30, 2001SaveLearn
Strong electron correlations in cobalt valence tautomersWe have examined cobalt based valence tautomer molecules such as Co(SQ)2(phen) using density functional theory (DFT) and variational configuration interaction (VCI) approaches based upon a model…M. X. LaBute, R. V. Kulkarni, R. G. Endres et al.·Oct 29, 2001SaveLearn
Onset of dissipation in ballistic atomic wiresElectronic transport at finite voltages in free-standing gold atomic chains of up to 7 atoms in length is studied at low temperatures using a scanning tunneling microscope (STM). The conductance vs…N. Agrait, C. Untiedt, G. Rubio-Bollinger et al.·Oct 29, 2001SaveLearn
Analytic approximations to Kelvin functions with applications to electromagneticsWe present analytical approximations for the real Kelvin function ber(x) and the imaginary Kelvin function bei(x), using the two-point quasifractional approximation procedure. We have applied these…L Brualla, P Martin·Oct 29, 2001SaveLearn
The role of the initial state in the collapse of a Bose condensed gasThe stability of a Bose condensed gas with a negative scattering length is studied with regard to the role played by the initial state. A trapped ideal gas ground state is shown to be unstable when…Thorsten Koehler·Oct 29, 2001SaveLearn
A microscopic quantum dynamics approach to the dilute condensed Bose gasWe derive quantum evolution equations for the dynamics of dilute condensed Bose gases. The approach contains, at different orders of approximation, for cases close to equilibrium, the Gross…Thorsten Koehler, Keith Burnett·Oct 29, 2001SaveLearn
Comment on PRB 59, 9195 (1999) and 62, 14061 (2000) by D. S. Golubev and A. D. Zaikin, and on cond-mat/0110495 by D.S. Golubev, A.D. Zaikin, and Gerd SchönThe relation between "non-perturbative analysis" of low temperature dephasing and the perturbation theory is discussed. Contributions missed in each order of the perturbation theory due to…I. L. Aleiner, B. L. Altshuler, M. G. Vavilov·Oct 28, 2001SaveLearn
A Four Dimensional Generalization of the Quantum Hall EffectWe construct a generalization of the quantum Hall effect, where particles move in four dimensional space under a SU(2) gauge field. This system has a macroscopic number of degenerate single particle…Shou-Cheng Zhang, Jiangping Hu·Oct 27, 2001SaveLearn
Photon Filamentation in Resonant Media with High Fresnel NumbersThe phenomenon of turbulent photon filamentation occurs in lasers and other active optical media at high Fresnel numbers. A description of this phenomenon is suggested. The solutions to evolution…V. I. Yukalov·Oct 26, 2001SaveLearn
The effect of pressure on statics, dynamics and stability of multielectron bubblesThe effect of pressure and negative pressure on the modes of oscillation of a multi-electron bubble in liquid helium is calculated. Already at low pressures of the order of 10-100 mbar, these effects…J. Tempere, Isaac F. Silvera, J. T. Devreese·Oct 26, 2001SaveLearn
Spin Correlation Effects In a One Dimensional Electron GasThe Singwi, Sjolander, Tosi, Land (SSTL) approach is generalized to study the spin correlation effects in a one dimensional electron gas. It is shown that the SSTL approach is capable of generating…Murat Tas, Mehmet Tomak·Oct 26, 2001SaveLearn
Spin precession in disordered systems: Anomalous relaxation due to heavy tailed field distributionsWe investigate spin precession in the presence of randomly distributed field sources. Their fields hi reorient by thermally activated transitions and decrease as r-mu with the distance from the…Falk Scheffler, Philipp Maass·Oct 26, 2001SaveLearn
Nature of order from random two-body interactionsWe investigate the origin of order in the low-lying spectra of many-body systems with random two-body interactions. Our study based both on analytical as well as on numerical arguments shows that…S. Drozdz, M. Wojcik·Oct 26, 2001SaveLearn
Periodic orbit analysis of an elastodynamic resonator using shape deformationWe report the first definitive experimental observation of periodic orbits (POs) in the spectral properties of an elastodynamic system. The Fourier transform of the density of flexural modes show…T. Neicu, A. Kudrolli·Oct 25, 2001SaveLearn