Angular dependence of spin-orbit spin-transfer torques

Ki Seung Lee, Dongwook Go, Aurélien Manchon, Paul M. Haney, M. D. Stiles, Hyun Woo Lee, Kyoung Jin Lee

Research output: Contribution to journalArticle

45 Citations (Scopus)

Abstract

In ferromagnet/heavy-metal bilayers, an in-plane current gives rise to spin-orbit spin-transfer torque, which is usually decomposed into fieldlike and dampinglike torques. For two-dimensional free-electron and tight-binding models with Rashba spin-orbit coupling, the fieldlike torque acquires nontrivial dependence on the magnetization direction when the Rashba spin-orbit coupling becomes comparable to the exchange interaction. This nontrivial angular dependence of the fieldlike torque is related to the Fermi surface distortion, determined by the ratio of the Rashba spin-orbit coupling to the exchange interaction. On the other hand, the dampinglike torque acquires nontrivial angular dependence when the Rashba spin-orbit coupling is comparable to or stronger than the exchange interaction. It is related to the combined effects of the Fermi surface distortion and the Fermi sea contribution. The angular dependence is consistent with experimental observations and can be important to understand magnetization dynamics induced by spin-orbit spin-transfer torques.

Original languageEnglish
Article number144401
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume91
Issue number14
DOIs
Publication statusPublished - 2015 Apr 6

    Fingerprint

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Electronic, Optical and Magnetic Materials

Cite this