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arXiv · 2412.09192

Twist-induced spin splitting and spin-Hall-like effect in antiferromagnetic bilayers

Zhigang Song·Xiuying Zhang·Julian Klein·Jonathan Curtis·Frances M. Ross·Prineha Narang
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Abstract

Momentum-resolved spin-polarized bands are a key ingredient in many proposed spintronic devices, but their existence often relies on lattice commensurability or strong spin-orbit coupling. By a large-scale DFT calculation (up to 4212 atoms), we propose a way to realize strongly spin-polarized bands in the absence of these ingredients by twisting monolayers of van der Waals magnetic semiconductor CrSBr. Furthermore, due to the highly anisotropic electronic transport in this material, the twist-induced electronic transport becomes strongly coupled to the spin transport. We show that an in-plane electric field induces a transverse spin current, manifesting a twist-tunable spin-Hall effect in the absence of spin-orbit coupling. Using highthroughput computations, we also identify 231 other material candidates out of a set of 6000 magnetic two-dimensional materials, which satisfy the necessary conditions to realize this behavior, paving the way to widespread application of twist-tunable spin transport.

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Zhigang Song, Xiuying Zhang, Julian Klein, Jonathan Curtis, Frances M. Ross, Prineha Narang. 2024-12-12. Twist-induced spin splitting and spin-Hall-like effect in antiferromagnetic bilayers. https://arxiv.org/abs/2412.09192

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