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arXiv · 1702.02518

Non-local field-like spin-orbit torques in Rashba systems: an ab-initio study of Ag$_{2}$Bi/Ag/Fe film

Guillaume Géranton·Bernd Zimmermann·Nguyen H. Long·Phivos Mavropoulos·Stefan Blügel·Frank Freimuth·Yuriy Mokrousov
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Abstract

We investigate from first principles the field-like spin-orbit torques (SOTs) in a Ag$_{2}$Bi-terminated Ag(111) film grown on ferromagnetic Fe(110). We find that a large part of the SOT arises from the spin-orbit interaction (SOI) in the Ag$_{2}$Bi layer far away from the Fe layers. These results clearly hint at a long range spin transfer in the direction perpendicular to the film that does not originate in the spin Hall effect. In order to bring evidence of the non-local character of the computed SOT, we show that the torque acting on the Fe layers can be engineered by the introduction of Bi vacancies in the Ag$_{2}$Bi layer. Overall, we find a drastic dependence of the SOT on the disorder type, which we explain by a complex interplay of different contributions to the SOT in the Brillouin zone.

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Guillaume Géranton, Bernd Zimmermann, Nguyen H. Long, Phivos Mavropoulos, Stefan Blügel, Frank Freimuth, Yuriy Mokrousov. 2017-02-08. Non-local field-like spin-orbit torques in Rashba systems: an ab-initio study of Ag$_{2}$Bi/Ag/Fe film. https://doi.org/10.1103/physrevb.95.134449

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