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arXiv · 2505.06622

Optically induced spin Hall current in Janus transition-metal dichalcogenides

Tomoaki Kameda·Katsunori Wakabayashi
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Abstract

Monolayer Janus transition-metal dichalcogenides (TMDCs), such as WSeTe, exhibit Rashba-type spin-orbit coupling (SOC) due to broken out-of-plane mirror symmetry. Here, we theoretically demonstrate that pure spin Hall currents can be generated under light irradiation based on a tight-binding model. Rashba-type SOC plays a crucial role in determining the spin polarization direction and enhancing the generation efficiency of pure spin Hall currents. Our findings establish Janus TMDCs as promising materials for next-generation optospintronic devices.

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Tomoaki Kameda, Katsunori Wakabayashi. 2025-05-10. Optically induced spin Hall current in Janus transition-metal dichalcogenides. https://doi.org/10.1103/physrevb.111.195425

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