Anisotropic nonrelativistic charge-to-spin conversion in altermagnets

TL;DR

This paper investigates the anisotropic nonrelativistic charge-to-spin conversion in altermagnets, revealing highly directional efficiency variations and providing analytical formulas and first-principles calculations to understand this phenomenon.

Contribution

It introduces a theoretical framework and computational analysis for anisotropic charge-to-spin conversion in altermagnets, highlighting its potential for spintronic applications.

Findings

Conversion efficiency varies from zero to tens of percent depending on current direction.

Analytical formulas for anisotropic conversion ratio are derived.

First-principles calculations confirm the high anisotropy in selected altermagnets.

Abstract

The charge-to-spin conversion provides an efficient way to manipulate the magnetization by electrical means. In this work, we report on a study on the anisotropic nonrelativistic charge-to-spin conversion response to the current direction in altermagnets. Based on the general group-theoretical analysis, we derive analytical formulas for the anisotropic conversion ratio and identify its maximum value. We then exemplify those phenomena in representative altermagnets based on the density functional theory calculations. The highly anisotropic charge-to-spin conversion efficiency, varying from zero to several tens of percent, was demonstrated. Our work shines more light on the exploration of the nonrelativistic generation of spin currents in altermagnets.