Bose-Einstein Condensation in a Random Potential
Abstract Book of the XXIII IUPAP International Conference on Statistical Physics, Genova, Italy, (9-13 July 2007)Abstract
This talk reviews recent progress in the theory of Bose gases moving in
a frozen disorder potential which arises either artifically with laser
speckles or naturally in wire traps.
At first, we determine perturbatively the shift of the temperatures $T_c$ and $T_s$ which characterize the onset of
Bose-Einstein condensation and superfluidity, respectively,
for an ultracold dilute atomic gas in a harmonic trap
due to weak disorder. To this end we treat
both a Gaussian and a Lorentzian spatial correlation for the quenched
disorder potential.
Then we develop a Hartree-Fock mean-field theory
for a homogeneous disordered Bose gas by invoking the replica method.
Within this non-perturbative approximation scheme we find the phase boundaries
for the gas, the superfluid phase as well as the Bose-glass phase.