Magnetotransport properties of noble metals containing rare-earth impurities. I. Quadrupole scattering by rare-earth impurities in gold

Abstract
We report measurements of the magnetoresistance of gold containing rare-earth impurities in longitudinal and transverse magnetic fields. For rare-earths with orbital magnetism the dominant effect is an anisotropic magnetoresistance due to the scattering of the conduction electrons by the electric quadrupole moment of the 4f shell. This effect vanishes for gadolinium impurities (no quadrupole moment). We present a model of the anisotropic magnetoresistance induced by quadrupole scattering. From the analysis of the experimental results we derive the strength of the interaction of the conduction electrons with the quadrupole moment of the 4f shell.