2001/08/31 by K. Ziegler
Physics and Astronomy · #cond-mat.stat-mech
published as Journ. Low Temp. Phys. 126, 1431 (2002) · 14 pages, 1 figure
arxiv created 2001/10/23 · arxiv updated 2009/11/30
A grand canonical system of hard-core bosons in an optical lattice is considered. The bosons can occupy randomly N equivalent states at each lattice site. The limit N→∞ is solved exactly in terms of a saddle-point integration, representing a weakly-interacting Bose gas. At T=0 there is only a condensate in the limit N→∞. Corrections in 1/N increase the total density of bosons but suppress the condensate. This indicates a depletion of the condensate due to increasing interaction at finite values of N.