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Phase separation in the bosonic Hubbard model with ring exchange

V. Rousseau·G. G. Batrouni·R. T. Scalettar
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Abstract

We show that soft core bosons in two dimensions with a ring exchange term exhibit a tendency for phase separation. This observation suggests that the thermodynamic stability of normal bose liquid phases driven by ring exchange should be carefully examined.

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V. Rousseau, G. G. Batrouni, R. T. Scalettar. 2003-12-01. Phase separation in the bosonic Hubbard model with ring exchange. https://doi.org/10.1103/physrevlett.93.110404

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