Speaker
Dr
Konstantin Krutitsky
(Universität Duisburg-Essen)
Description
We have studied the phase diagram of a quasi-two-dimensional
interacting Bose gas at zero temperature in the presence of
random potential created by laser speckles. The superfluid
fraction and the fraction of particles with zero momentum
are obtained within the mean-field Gross-Pitaevskii theory
and in diffusion Monte Carlo simulations. We find a smooth
crossover from the superfluid to the insulating state, when
the strength of the disorder grows. Estimations of the
crossover lines are compared with the predictions of the
percolation theory in the Thomas-Fermi approximation.
Analytical expressions for zero-momentum fraction and
superfluid fraction are derived in the limit of weak
disorder and weak interactions within the framework of the
Bogoliubov theory. Limits of validity of various
approximations are discussed.
Primary author
Dr
Konstantin Krutitsky
(Universität Duisburg-Essen)
