Irreversibility of infinite range spin glasses

Abstract

By employing the ‘‘slow-cooling’’ iterative solution of the mean field equations, we study the free energy surface of the isotropic, infinite range Ising and Heisenberg spin glasses with up to 800 spins. Ising model results for the field cooled and zero field cooled magnetizations as well as the magnetic hysteresis loops are similar to those found for the short ranged model. However, the results for the Heisenberg model depend strongly on the range of the interaction. The infinite range model shows macroscopic irreversiblity, in contrast to the short range isotropic Heisenberg case which has no irreversibility.