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arXiv · 2004.09852

Surface Rashba-Edelstein Spin-Orbit Torque Revealed by Molecular Self-Assembly

Satoshi Haku·Atsushi Ishikawa·Akira Musha·Hiroyasu Nakayama·Takashi Yamamoto·Kazuya Ando
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Abstract

We report the observation of a spin-orbit torque (SOT) originating from the surface Rashba-Edelstein effect. We found that the SOT in a prototypical spin-orbitronic system, a Pt/Co bilayer, can be manipulated by molecular self-assembly on the Pt surface. This evidences that the Rashba spin-orbit coupling at the Pt surface generates a sizable SOT, which has been hidden by the strong bulk and interface spin-orbit coupling. We show that the molecular tuning of the surface Rashba-Edelstein SOT is consistent with density functional theory calculations. These results illustrate the crucial role of the surface spin-orbit coupling in the SOT generation, which alters the landscape of metallic spin-orbitronic devices.

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Satoshi Haku, Atsushi Ishikawa, Akira Musha, Hiroyasu Nakayama, Takashi Yamamoto, Kazuya Ando. 2020-04-21. Surface Rashba-Edelstein Spin-Orbit Torque Revealed by Molecular Self-Assembly. https://arxiv.org/abs/2004.09852

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