Prediction of Purely Interfacial Giant Antidamping Spin-Orbit Torque induced by Skew Scattering*

Spin angular momentum transfer between conduction electrons and localized magnetic moments gives rise to interesting nonequilibrium spin-orbit coupling phenomena, including current-induced antidamping spin-orbit torque (ASOT), considered to be a crucial ingredient in next-generation spin memories [1]. In this talk, we present a new microscopic framework that accounts for intrinsic and extrinsic transport effects on equal footing and nonperturbatively, for the first time [2-3]. Calculations performed for generic k-p models of Rashba interfaces discloses a ubiquitous (yet hitherto neglected) mechanism for the generation of prominent interfacial ASOT: skew scattering activated by the out-of-plane tilting of spin-orbit textures in k -space. Our findings show that current-carrying Rashba interfaces can exert strong ASOT even in the absence of magnetic scattering centers and bulk spin-orbit-coupled transport mechanisms.

[1] A. Manchon et al, Rev. Mod. Phys., 91, 035004 (2019).
[2] F. Sousa, G. Tatara, A. Ferreira, pre-print: arXiv:2005.09670
[3] A. Veneri et al, to be published (2020)