A magnetic cluster model for spin glasses

Abstract

A model for spin glasses is proposed in which spins whose RKKY interactions exceed thermal energies define magnetic clusters. Percolation theory determines the spin glass temperature T_g below which an infinite cluster forms. With suitable anisotropy assumptions the infinite cluster will be superparamagnetically blocked, giving a cusped susceptibility at T_g. A collinear distribution in each cluster gives an effectively one-dimensional internal field at low temperatures. The model predicts Blandin-Souletie scaling at all temperatures and a T^-1 specific heat tail.