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arXiv · 2004.01064

Reversible edge spin currents in antiferromagnetically proximitized dichalcogenides

Abstract

We explore proximity effects on transition metal dichalcogenide ribbons deposited on antiferromagnetic (AFM) insulating substrates. We model these hybrid heterostructures using a tight-binding model that incorporates exchange and Rashba fields induced by proximity to the AFM material. The robust edge states that disperse in the midgap of the dichalcogenide are strongly affected by induced exchange fields that reflect different AFM ordering in the substrate. This results in enhanced spin-orbit coupling effects and complex spin projection content for states on zigzag ribbon edges. Gated systems that shift the Fermi level in the midgap range are also shown to exhibit spin polarized currents on these edges. Antiparallel exchange fields along the edge results in spin currents that can reverse polarization with the applied field. The added functionality of these hybrid structures can provide spintronic devices and versatile platforms to further exploit proximity effects in diverse material systems.

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Natalia Cortés, O. Ávalos-Ovando, S. E. Ulloa. 2020-04-02. Reversible edge spin currents in antiferromagnetically proximitized dichalcogenides. https://doi.org/10.1103/physrevb.101.201108

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