Microscopic theory of the residual surface resistivity of Rashba electrons

TL;DR

This paper derives a microscopic theory for the residual surface resistivity of Rashba electrons scattering at magnetic impurities, analyzing how spin-orbit strength and impurity magnetization influence resistivity and related effects.

Contribution

It provides a new microscopic expression for residual resistivity tensor in Rashba systems, including effects of impurity magnetization and spin-orbit interaction.

Findings

Resistivity decreases with increasing spin-orbit strength.

Magnetic impurities induce planar Hall effect and anisotropic magnetoresistance.

Functional forms describe resistivity anisotropy relative to impurity magnetization direction.

Abstract

A microscopic expression of the residual electrical resistivity tensor is derived in linear response theory for Rashba electrons scattering at a magnetic impurity with cylindrical or non-cylindrical potential. The behavior of the longitudinal and transversal residual resistivity is computed for an Fe impurity at the Au(111) surface. We studied the evolution of the resistivity tensor elements as function of the Rashba spin-orbit strength and the magnetization direction of the impurity. We found that the absolute values of longitudinal resistivity reduces with increasing spin-orbit strength of the substrate and that the scattering of the conduction electrons at magnetic impurities with magnetic moments pointing in directions not perpendicular to the surface plane produce a planar Hall effect and an anisotropic magnetoresistance even if the impurity carries no spin-orbit interaction. Functional forms are provided describing the anisotropy of the planar Hall effect and the anisotropic magnetoresistance with respect to the direction of the impurity moment. In the limit of no spin-orbit interaction and a non-magnetic impurity of cylindrical symmetry, the expression of the residual resistivity of a two-dimensional electron-gas has the same simplicity and form as for the three-dimensional electron gas [J. Friedel, NuovoCimento Suppl. 7, 287 (1958)] and can also be expressed in terms of scattering phase shifts.