ATOMIC POWER GLASS

Posted in: Technology in visakebin's Blog

arXiv:0805.0488 (May 2008)

Physical replicas and the Bose-glass in cold atomic gases

S. Morrison, A. Kantian, A. J. Daley, H. G. Katzgraber, M. Lewenstein, H. P. Büchler and P. Zoller

Institute for Theoretical Physics, University of Innsbruck, Technikerstr. 25, A-6020 Innsbruck, Austria, and Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences, A-6020 Innsbruck, Austria
ICFO-Institut de Ciències Fotòniques, Parc Mediterrani de la Tecnologia, E-08860 Castelldefels (Barcelona), Spain, and ICREA - Instituciò Catala de Ricerca i Estudis Avancats, 08010 Barcelona, Spain
Theoretische Physik, ETH Zurich, CH-8093 Zürich, Switzerland
Institute for Theoretical Physics III, University of Stuttgart, Pfaffenwaldring 57, 70550 Stuttgart, Germany

Received. 05 May 2008 Last updated. 05 May 2008

Abstract. We study cold atomic gases in a disorder potential and analyze the correlations between different systems subjected to the same disorder landscape. Such independent copies with the same disorder landscape are known as replicas. While in general these are not accessible experimentally in condensed matter systems, they can be realized using standard tools for controlling cold atomic gases in an optical lattice. Of special interest is the overlap function which represents a natural order parameter for disordered systems and is a correlation function between the atoms of two independent replicas with the same disorder. We demonstrate an efficient measurement scheme for the determination of this disorder-induced correlation function. As an application, we focus on the disordered Bose-Hubbard model and determine the overlap function within perturbation theory and a numerical analysis. We find that the measurement of the overlap function allows for the identification of the Bose-glass phase in certain parameter regimes.

Categories. cond-mat.other cond-mat.dis-nn

Subject. Other; Disordered Systems and Neural Networks

Comment. 16 pages, 6 figures License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/