Crossover scaling function for exchange anisotropy: Heisenberg toXY-like crossover

Abstract
The crossover behavior of the susceptibility χxx of the classical Heisenberg model with XY -like anisotropic exchange coupling is studied following the methods of Pfeuty, Jasnow, and Fisher. The universal scaling function is obtained and, from it, the crossover of the effective susceptibility exponent γeff is found.