Disorder-induced shift of condensation temperature for dilute trapped Bose gasesM. Timmer, A. Pelster and R. Graham
Universität Duisburg-Essen, Campus Duisburg, Fachbereich Physik Lotharstrasse 1, 47048 Duisburg, Germany
received 20 July 2006; accepted in final form 4 October 2006
published online 8 November 2006
We determine the leading shift of the Bose-Einstein condensation temperature for an ultracold dilute atomic gas in a harmonic trap due to weak disorder by treating both a Gaussian and a Lorentzian spatial correlation for the quenched disorder potential. Increasing the correlation length from values much smaller than the geometric mean of the trap scale and the mean particle distance to much larger values leads first to an increase of the positive shift to a maximum at this critical length scale and then to a decrease.
03.75.Hh - Static properties of condensates; thermodynamical, statistical, and structural properties.
64.60.Cn - Order-disorder transformations; statistical mechanics of model systems.
© EDP Sciences 2006