Resistivity of spin-glasses

Abstract

We analyze experimental data on the temperature-dependent part of the resistivity of $\mathrm{Au}\mathrm{Fe}$, $\mathrm{Cu}\mathrm{Mn}$, $\mathrm{Ag}\mathrm{Mn}$, $\mathrm{Au}\mathrm{Mn}$, and $\mathrm{Au}\mathrm{Cr}$ spin-glass alloys, using a model derived from the excitation approach of Walker and Walstedt. The model gives a satisfactory description of the experimental behavior for all the alloys. We find an energy scaling parameter for the excitation density of states that turns out to be approximately proportional to the spin-glass freezing temperature $T_g$. From the resistivity results we can estimate the local spin-relaxation time.