Dzyaloshinskii-Moriya spin density by skew scattering

TL;DR

This paper predicts an anisotropic conduction electron spin density induced by skew scattering in metals with heavy magnetic impurities, revealing a new mechanism for Dzyaloshinskii-Moriya interactions influenced by spin-orbit coupling.

Contribution

It introduces a model showing how skew scattering causes a non-collinear spin density, extending the understanding of DMI in metals with heavy magnetic impurities.

Findings

DM-SD is rotated by skew scattering, not aligned with magnetic moments.

The model links lanthanide spin to DMI strength and polarization.

Potential for controlling anisotropic magnetic couplings via impurity spin.

Abstract

Anisotropic exchange couplings, such as the Dzyaloshinskii-Moriya interaction (DMI), have played a vital role in the formation and dynamics of spin textures. This work predicts an anisotropic conduction electron spin density in metals with heavy magnetic impurities. The polarization of this $Dzyaloshinskii$-$Moriya$ $spin$ $density$ (DM-SD) is not collinear to the localized magnetic moments but rotated by the spin-dependent skew scattering of heavy atoms. The DM-SD induces the DMI between magnetic moments in metals and, therefore, it is the anisotropic extension of the Rutherman-Kittel-Kasuya-Yoshida spin density. Our model consists of two localized magnetic moments, one with a large spin-orbit coupling (a lanthanide or rare earth), in a free electron gas. The lanthanide spin controls the DM-SD strength and polarization, promising a flexible control mechanism for anisotropic couplings.