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arXiv · 2606.19274

Theory of nonlinear spin transport in chiral conductors

Lorenzo Cavicchi·Marco Polini
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Abstract

The chirality-induced spin selectivity (CISS) effect, discovered by Naaman and collaborators in 1999, describes the emergence of a finite spin polarization in response to current flow through a chiral electronic system. While extensive experimental studies have verified the presence of CISS in molecular systems and, more recently, in chiral materials, a complete microscopic understanding of this effect remains elusive. In this work, we propose a theoretical framework linking the CISS effect to the orbital Edelstein effect. In the latter, a drive current induces a finite orbital magnetization, even in the absence of spin-orbit coupling. Our non-equilibrium theory naturally explains key features of the CISS effect: its persistence in systems with weak or vanishingly small spin-orbit coupling and its connection to natural optical activity, a distinctive signature of chiral systems.

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Lorenzo Cavicchi, Marco Polini. 2026-06-17. Theory of nonlinear spin transport in chiral conductors. https://arxiv.org/abs/2606.19274

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