Mean-field theory of freezing temperatures of two-component metallic spin glasses.

Abstract

A mean-field approach which emphasizes spin-spin pair correlations is used to calculate the freezing temperature ${\mathit{T}}_{\mathit{g}}$ of two-component metallic spin glasses. We calculate the variation in ${\mathit{T}}_{\mathit{g}}$ as a function of the ratio of concentrations of the two magnetic species. Finite-temperature effects and intrinsic sd scattering of electrons play important roles in establishing the trends exhibited by ${\mathit{T}}_{\mathit{g}}$. A clear physical interpretation is given which provides insight into the behavior of ${\mathit{T}}_{\mathit{g}}$ in real, two-component spin glasses. The theory satisfactorily reproduces experimental results without the use of any adjustable parameters. We also predict how ${\mathit{T}}_{\mathit{g}}$ will behave if the concentrations of the two species are varied while the ratio ${\mathit{c}}_{2}$/${\mathit{c}}_{1}$ of the concentrations is held fixed.