Resistivity of SomeCuAuFeAlloys

Abstract

The electrical resistivity of a series of $\mathrm{CuAu}\mathrm{Fe}$ alloys, containing 0, 5, 10, and 100 at.% Au, has been measured over the temperature range 0.5-300 °K, and the results are compared with recent theoretical predictions of the resistance anomaly associated with the formation of the spin-compensated state. From such a comparison, the Kondo temperature $T_K$ is found to decrease rapidly with increasing Au concentration from 24 °K in $\mathrm{Cu}\mathrm{Fe}$ to 0.24 °K in $\mathrm{Au}\mathrm{Fe}$. Although a dependence of the form $A-B{\left(\frac{T}{T_K}\right)}^2\ln {\left(\frac{T}{T_K}\right)}^2$ is found to fit the results of the $\mathrm{CuAu}\mathrm{Fe}$ alloys over a wide range of temperatures, this does not describe the $\mathrm{Cu}\mathrm{Fe}$ results in the low-temperature limit, where a parabolic dependence $C-D{\left(\frac{T}{T_K}\right)}^2$ is observed for $\frac{T}{T_K}<0.06\mathrm{}$. An expression of the form $E-F{\left(1+\frac{S(S+1\mathrm{})\mathrm{}{\pi }^2}{{\left[\ln \right(\frac{T}{T_K}\left)\right]}^2}\right)}^{\frac{-1\mathrm{}}{2}}$ describes the Au results and those of the $\mathrm{CuAu}\mathrm{Fe}$ alloys at $T>\mathrm{}{T}_K$ with the spin $S=0.77\mathrm{}\pm 0.25$ if suitable corrections are made for deviations from Matthiessen's rule in the temperature region where phonon scattering is significant.