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On Defect-Mediated Transitions in Bosonic Planar Lattices

A. Trombettoni·A. Smerzi·P. Sodano
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Abstract

We discuss the finite-temperature properties of Bose-Einstein condensates loaded on a 2D optical lattice. In an experimentally attainable range of parameters the system is described by the XY model, which undergoes a Berezinskii-Kosterlitz-Thouless (BKT) transition driven by the vortex pair unbinding. The interference pattern of the expanding condensates provides the experimental signature of the BKT transition: near the critical temperature, the k=0 component of the momentum distribution sharply decreases.

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A. Trombettoni, A. Smerzi, P. Sodano. 2005-06-04. On Defect-Mediated Transitions in Bosonic Planar Lattices. https://arxiv.org/abs/cond-mat/0506108

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