Spin-orbit torque emerging from orbital textures in centrosymmetric materials

Luis M. Canonico; Jose H. García; Stephan Roche

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arXiv · 2307.14673

Spin-orbit torque emerging from orbital textures in centrosymmetric materials

Luis M. Canonico·Jose H. García·Stephan Roche

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Abstract

We unveil a hitherto concealed spin-orbit torque mechanism driven by orbital degrees of freedom in centrosymmetric two-dimensional transition metal dichalcogenides (focusing on PtSe${}_2$ ). Using first-principles simulations, tight-binding models and large-scale quantum transport calculations, we show that such a mechanism fundamentally stems from a spatial localization of orbital textures at opposite sides of the material, which imprints their symmetries onto spin-orbit coupling effects, further producing efficient and tunable spin-orbit torque. Our study suggests that orbital-spin entanglement at play in centrosymmetric materials can be harnessed as a resource for outperforming conventional spin-orbit torques generated by the Rashba-type effects.

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Luis M. Canonico, Jose H. García, Stephan Roche. 2023-07-27. Spin-orbit torque emerging from orbital textures in centrosymmetric materials. https://arxiv.org/abs/2307.14673

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