A cumulant expansion to the glass-like phase in the random-bond Ising model

Abstract

A random Ising magnet with ferro- and antiferromagnetic interactions J_A and J_B, is treated by the method of a modified cumulant expansion regarding the effective field and its square as random variables. Phase boundaries between the glass-like phase (GLP) and the ferro- and the antiferromagnetic phases, are determined. It is shown that the susceptibility and the specific heat have cusps at the transition temperature T_G between the glass-like phase and paramagnetic phase.