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arXiv · 2606.27121

Magnetoresistance in chiral systems driven by inter-band spin-orbit coupling

Misa Nozaki·Takatoshi Fujita
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Abstract

Chiral-induced spin selectivity (CISS), in which electrons transmitted through nonmagnetic chiral materials exhibit strong spin-dependent transport, has attracted growing interest for spintronic applications. However, a quantitative understanding of CISS remains elusive, partly because most previous studies rely on single-band models. In this work, we theoretically investigate multi-band effects on magnetoresistance (MR)-CISS, which is typically observed in experiments using magnetic conductive atomic force microscopy. To evaluate the spin polarization in MR-CISS, we simulate the nonequilibrium steady-state current using the Gorini-Kossakowski-Sudarshan-Lindblad master equation. We find that spin polarization exceeding 25% can be achieved for realistic inter-band spin-orbit coupling strengths in the presence of on-site Coulomb interactions. These findings highlight the crucial role of inter-band spin-orbit coupling in the mechanism of CISS.

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Misa Nozaki, Takatoshi Fujita. 2026-06-29. Magnetoresistance in chiral systems driven by inter-band spin-orbit coupling. https://arxiv.org/abs/2606.27121

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