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arXiv · cond-mat/0605163

Mean-field phase diagram of disordered bosons in a lattice at non-zero temperature

Abstract

Bosons in a periodic lattice with on-site disorder at low but non-zero temperature are considered within a mean-field theory. The criteria used for the definition of the superfluid, Mott insulator and Bose glass are analysed. Since the compressibility does never vanish at non-zero temperature, it can not be used as a general criterium. We show that the phases are unambiguously distinguished by the superfluid density and the density of states of the low-energy exitations. The phase diagram of the system is calculated. It is shown that even a tiny temperature leads to a significant shift of the boundary between the Bose glass and superfluid.

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K. V. Krutitsky, A. Pelster, R. Graham. 2006-09-12. Mean-field phase diagram of disordered bosons in a lattice at non-zero temperature. https://doi.org/10.1088/1367-2630%2F8%2F9%2F187

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