Unified approach to some transport and EPR properties of noble metals with rare-earth impurities

Abstract

Both magnetotransport and EPR experiments have shown the importance of the anisotropic character of the $k\ensuremath{-}f$ interaction between conduction and $4f$ electrons. For noble metals with rare-earth impurities the magnitude of the anisotropic terms can be understood in terms of the hybridization of the conduction electrons with the outer $5d$ electrons of the rare-earth impurities. To obtain a consistent description of the magnetotransport properties we have included the spin-orbit coupling of the $5d$ electrons as well as their crystal-field splitting. The various parameters entering our model have been determined by fitting the isotropic transport properties as well as the anisotropic magnetoresistance arising from quadrupole scattering and the Hall effect due to skew scattering. We have used this model to calculate the $5d$ virtual bound state contribution to the $g$ shift and linewidth of rare-earth impurities in noble metals. After estimating the $s$ contribution we obtain a consistent fit for the $g$ shift and linewidth of several rare earths in noble metals.