2006/05/31 by K. V. Krutitsky, A. Pelster, R. Graham · 1 citation
Physics and Astronomy · #cond-mat.dis-nn #cond-mat.other
paper · pdf · doi:10.1088/1367-2630/8/9/187
published as New J. Phys. 8, 187 (2006)
arxiv created 2006/09/12 · arxiv updated 2009/12/01
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.