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arXiv · 1312.2409

Spin-orbit torque opposing the Oersted torque in ultrathin Co/Pt bilayers

T. D. Skinner·M. Wang·A. T. Hindmarch·A. W. Rushforth·A. C. Irvine·D. Heiss·H. Kurebayashi·A. J. Ferguson
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Abstract

Current-induced torques in ultrathin Co/Pt bilayers were investigated using an electrically driven FMR technique. The angle dependence of the resonances, detected by a rectification effect as a voltage, were analysed to determine the symmetries and relative magnitudes of the spin-orbit torques. Both anti-damping (Slonczewski) and field-like torques were observed. As the ferromagnet thickness was reduced from 3 to 1 nm, the sign of the field-like torque reversed. This observation is consistent with the emergence of a Rashba spin orbit torque in ultra-thin bilayers.

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T. D. Skinner, M. Wang, A. T. Hindmarch, A. W. Rushforth, A. C. Irvine, D. Heiss, H. Kurebayashi, A. J. Ferguson. 2013-12-09. Spin-orbit torque opposing the Oersted torque in ultrathin Co/Pt bilayers. https://doi.org/10.1063/1.4864399

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