Thermodynamics of noninteracting bosonic gases in cubic optical lattices versus ideal homogeneous Bose gases (Q2794688)

The authors study the thermodynamical properties of non-interacting gases in a periodic lattice potential at arbitrary integer fillings, and compare them with that of ideal homogeneous gases. They derive explicit expressions for the thermodynamical quantities by performing exact numerical calculations. By means of these expressions, the dependence of entropy and energy on the temperature is found in the normal phase which is rather weak especially at large filling factors. In the Bose condensed phase, their power dependence on the reduced temperature is nearly linear. Moreover, the discontinuity is evaluated in the slope of the specific heat which turns out to be approximately the same as that of the ideal homogeneous Bose gas for filling factor \(\nu=1\).