The low temperature electrical resistivity of high purity Ag and Ag based alloys

Abstract

High resolution measurements have been made of the electrical resistivity of Ag and alloys of Ag with Au, Pd and Pt, over the temperature range 2K-20K. The samples had all been freed of Fe contamination, and their residual resistivities ranged from 1 n Omega cm to 1 mu Omega cm. Below 10K all samples showed an almost pure T⁴ temperature dependence. Breakdown of Matthiessen's rule was severe at all temperatures, for example at 4.2K the samples showed a temperature dependent part of the resistivity that varied by a factor of ten. Neither the temperature dependence nor the departures from Matthiessen's rule appear to be explicable in terms of currently accepted theories.