All electrical manipulation of magnetization dynamics in a ferromagnet by antiferromagnets with anisotropic spin Hall effects

TL;DR

This study demonstrates how antiferromagnets with anisotropic spin Hall effects can electrically manipulate magnetization dynamics in ferromagnets, revealing orientation-dependent spin torques and large tunable spin-orbit effects.

Contribution

It provides experimental evidence of anisotropic spin Hall effects in antiferromagnets and their influence on magnetization dynamics, supported by first-principles calculations.

Findings

Spin torques mainly from diffusive spin current transport.

Growth-orientation dependence of spin torques observed.

Anisotropy of spin Hall effect confirmed by calculations.

Abstract

We investigate spin-orbit torques of metallic CuAu-I-type antiferromagnets using spin-torque ferromagnetic resonance tuned by a dc-bias current. The observed spin torques predominantly arise from diffusive transport of spin current generated by the spin Hall effect. We find a growth-orientation dependence of the spin torques by studying epitaxial samples, which may be correlated to the anisotropy of the spin Hall effect. The observed anisotropy is consistent with first-principles calculations on the intrinsic spin Hall effect. Our work demonstrates large tunable spin-orbit effects in magnetically-ordered materials.