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arXiv · 1111.3196

New mechanism for generating spin transfer torque without charge current

G. Autès·J. Mathon·A. Umerski
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Abstract

A new physical mechanism for generating spin-transfer torque is proposed. It is due to interference of bias driven nonequilibrium electrons incident on a switching junction with the electrons reflected from an insulating barrier inserted in the junction after the switching magnet. It is shown using the rigorous Keldysh formalism that this new out-of-plane torque $T_{\perp}$ is proportional to an applied bias and is as large as the torque in a conventional junction generated by a strong charge current. However, the charge current and the in-plane torque $T_{\parallel}$ are almost completely suppressed by the insulating barrier. This new junction thus offers the highly applicable possibility of bias-induced switching of magnetization without charge current.

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G. Autès, J. Mathon, A. Umerski. 2011-11-14. New mechanism for generating spin transfer torque without charge current. https://doi.org/10.1063/1.3689745

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