Giant chirality-induced spin polarization in twisted transition metal dichalcogenides

Guido Menichetti; Lorenzo Cavicchi; Leonardo Lucchesi; Fabio Taddei; Giuseppe Iannaccone; Pablo Jarillo-Herrero; Claudia Felser; Frank H. L. Koppens; Marco Polini

doi:10.1016/j.newton.2025.100013

arXiv · 2312.09169

Giant chirality-induced spin polarization in twisted transition metal dichalcogenides

Guido Menichetti·Lorenzo Cavicchi·Leonardo Lucchesi·Fabio Taddei·Giuseppe Iannaccone·Pablo Jarillo-Herrero·Claudia Felser·Frank H. L. Koppens·Marco Polini

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Abstract

Chirality-induced spin selectivity (CISS) is an effect that has recently attracted a great deal of attention in chiral chemistry and that remains to be understood. In the CISS effect, electrons passing through chiral molecules acquire a large degree of spin polarization. In this work we study the case of atomically-thin chiral crystals created by van der Waals assembly. We show that this effect can be spectacularly large in systems containing just two monolayers, provided they are spin-orbit coupled. Its origin stems from the combined effects of structural chirality and spin-flipping spin-orbit coupling. We present detailed calculations for twisted homobilayer transition metal dichalcogenides, showing that the chirality-induced spin polarization can be giant, e.g. easily exceeding $50\%$ for ${\rm MoTe}_2$. Our results clearly indicate that twisted quantum materials can operate as a fully tunable platform for the study and control of the CISS effect in condensed matter physics and chiral chemistry.

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Guido Menichetti, Lorenzo Cavicchi, Leonardo Lucchesi, Fabio Taddei, Giuseppe Iannaccone, Pablo Jarillo-Herrero, Claudia Felser, Frank H. L. Koppens, Marco Polini. 2024-01-23. Giant chirality-induced spin polarization in twisted transition metal dichalcogenides. https://doi.org/10.1016/j.newton.2025.100013

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