Eur. Phys. J. B (2014) 87: 243
https://doi.org/10.1140/epjb/e2014-50404-x

Regular Article

First principle explanation of phase transition for Bose-Einstein condensates in optical lattices

Department of Physics, Computer Sciences and Mathematics, University of Modena e Reggio Emilia, Via Campi 213/B, 41125 Modena, Italy

^a e-mail: andrea.sacchetti@unimore.it

Received: 16 June 2014
Received in final form: 28 August 2014
Published online: 22 October 2014

Abstract

In this paper we consider Bose-Einstein condensates (BECs) in one-, two- and three-dimension lattice potentials. The key argument for the explanation of the transition from Superfluidity phase to Mott-Insulator phase is suggested to be the spontaneous symmetry breaking effect which occurs for critical values of the ratio between the on-site interaction term and the hopping matrix element. Such an effect can be directly seen in the Gross-Pitaevskii equation with double-well potentials and it also explains the different behavior between one-dimensional models and two/three-dimensional models.