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arXiv · 1802.01285

Intrinsic spin-orbit torque arising from Berry curvature in metallic-magnet/Cu-oxide interface

Tenghua Gao·Alireza Qaiumzadeh·Hongyu An·Akira Musha·Yuito Kageyama·Ji Shi·Kazuya Ando
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Abstract

We report the observation of the intrinsic damping-like spin-orbit torque (SOT) arising from the Berry curvature in metallic-magnet/CuO$_x$ heterostructures. We show that a robust damping-like SOT, an order of magnitude larger than a field-like SOT, is generated in the heterostructure despite the absence of the bulk spin-orbit effect in the CuO$_x$ layer. Furthermore, by tuning the interface oxidation level, we demonstrate that the field-like SOT changes drastically and even switches its sign, which originates from oxygen modulated spin-dependent disorder. These results provide an important information for fundamental understanding of the physics of the SOTs.

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Tenghua Gao, Alireza Qaiumzadeh, Hongyu An, Akira Musha, Yuito Kageyama, Ji Shi, Kazuya Ando. 2018-02-05. Intrinsic spin-orbit torque arising from Berry curvature in metallic-magnet/Cu-oxide interface. https://doi.org/10.1103/physrevlett.121.017202

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