arXiv:cond-mat/0610476 · Physical Review A

Mean-field phase diagram of cold lattice bosons in disordered potentials

Pierfrancesco Buonsante, Vittorio Penna, A. Vezzani, P. B. Blakie

Published Jul 3, 2007• 48 citations

Abstract

We address the phase diagram of the disordered Bose-Hubbard model that has been realized in several recent experiments in terms of optically trapped ultracold bosons. We show that a systematic description of all of the expected quantum phases can be obtained at both zero and finite temperature via a site-dependent decoupling mean-field approach. Also, we relate the boundaries of the Mott-insulating phase to an off-diagonal noninteracting Anderson model whose spectral features provide an avenue for determining the debated nature of the phase surrounding the Mott lobes. Our approach is simple yet effective, and scalable to systems with experimentally relevant sizes and features.

DOI: 10.1103/physreva.76.011602

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