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arXiv · 0810.3763

Feshbach-Einstein condensates

Valy G. Rousseau·Peter J. H. Denteneer
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Abstract

We investigate the phase diagram of a two-species Bose-Hubbard model describing atoms and molecules on a lattice, interacting via a Feshbach resonance. We identify a region where the system exhibits an exotic super-Mott phase and regions with phases characterized by atomic and/or molecular condensates. Our approach is based on a recently developed exact quantum Monte Carlo algorithm: the Stochastic Green Function algorithm with tunable directionality. We confirm some of the results predicted by mean-field studies, but we also find disagreement with these studies. In particular, we find a phase with an atomic but no molecular condensate, which is missing in all mean-field phase diagrams.

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Valy G. Rousseau, Peter J. H. Denteneer. 2008-12-09. Feshbach-Einstein condensates. https://doi.org/10.1103/physrevlett.102.015301

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