TwoDimensional System of HardCore Bosons
Abstract
As a model of a helium monolayer a system of hardcore bosons of mass m and diameter a constrained to motion in two dimensions is considered at absolute zero. In the lowdensity limit, the groundstate energy per particle and condensate depletion are found to be EN=2πℏ^{2}nmlnna^{2} and n_{0}=n(1+1lnna^{2}), where n is the areal density of the system. The expansion parameter 1lnna^{2} is approximately equal to unity for real helium monolayers. The variation of the above results with temperature is discussed for a system of finite size.
 Publication:

Physical Review A
 Pub Date:
 March 1971
 DOI:
 10.1103/PhysRevA.3.1067
 Bibcode:
 1971PhRvA...3.1067S