Magnetic Field Scaling in Spin Glasses and the Mean-Field Theory

Abstract

The scaling of the magnetic field dependence of the remanent magnetization for different temperatures and different spin-glass samples is studied. Particular attention is paid to the effect of the de Almeida-Thouless (AT) critical line on spin-glass dynamics. It is shown that results of the mean-field theory of aging phenomena, with two additional experimentally justified assumptions, predict $H/H_{AT}(T)$ scaling for remanent magnetization curves. Experiments on a single crystal Cu:Mn 1.5 at % sample in the temperature interval from $0.7T_{g}$ to $0.85T_{g}$ give results consistent with this scaling. Magnetization vs. field curves for different Cu:Mn and thiospinel samples also scale together. These experimental results support the predictions of the mean-field theory of aging phenomena.