We propose a simple analytical form of the partition function
for charged bosons localised in a random potential and
derive the consequent thermodynamics below the superfluid
transition temperature. In the low temperature limit, the
specific heat C depends on the localisation length exponent
ν: C is linear for ν ≤ 1, but for ν > 1 we obtain C ∝ T1/ .
This unusual sub-linear temperature dependence of the specific
heat has recently been observed in La2−xSrxCuO4 below
This is a pre-print. It is also available at: http://arxiv.org/abs/cond-mat/9712029.