Finite-Temperature Disordered Bosons in Two Dimensions
Giulio Bertoli, V. P. Michal, B. L. Altshuler +1 more
We study phase transitions in a two dimensional weakly interacting Bose gas in a random potential at finite temperatures. We identify superfluid, normal fluid, and insulator phases and construct the phase diagram. At T=0 one has a tricritical point where the three phases coexist. The truncation of the energy distribution at the trap barrier, which is a generic phenomenon in cold atom systems, limits the growth of the localization length and in contrast to the thermodynamic limit the insulator phase is present at any temperature.
arXiv:1708.03628•Physical Review Letters•Jul 18, 2018•17 citations