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arXiv · 2402.12353

Emergence of radial Rashba spin-orbit fields in twisted van der Waals heterostructures

Tobias Frank·Paulo E. Faria Junior·Klaus Zollner·Jaroslav Fabian
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Abstract

Rashba spin-orbit coupling is a quintessential spin interaction appearing in virtually any electronic heterostructure. Its paradigmatic spin texture in the momentum space forms a tangential vector field. Using first-principles investigations, we demonstrate that in twisted homobilayers and hetero-multilayers, the Rashba coupling can be predominantly radial, parallel to the momentum. Specifically, we study four experimentally relevant structures: twisted bilayer graphene (Gr), twisted bilayer WSe$_2$, and twisted multilayers WSe$_2$/Gr/WSe$_2$ and WSe$_2$/Gr/Gr/WSe$_2$. We show, that the Rashba spin-orbit field texture in such structures can be controlled by an electric field, allowing to tune it from radial to tangential. Such spin-orbit engineering should be useful for designing novel spin-charge conversion and spin-orbit torque schemes, as well as for controlling correlated phases and superconductivity in van der Waals materials.

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Tobias Frank, Paulo E. Faria Junior, Klaus Zollner, Jaroslav Fabian. 2024-02-19. Emergence of radial Rashba spin-orbit fields in twisted van der Waals heterostructures. https://arxiv.org/abs/2402.12353

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