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arXiv · 2503.04922

Lateral Exchange Bias for Néel-Vector Control in Atomically Thin Antiferromagnets

Abstract

Atomically thin van der Waals (vdW) magnets have emerged as a fascinating platform for the exploration of novel physical phenomena arising from their reduced dimensionality and exceptional material properties. Their single-crystalline nature and ultimate miniaturization position them as leading candidates for next-generation spintronic applications. Antiferromagnetic (AF) vdW magnets are of particular interest, as they combine the advantages of vdW magnets with the functionality of AF spintronics, offering unique opportunities for ultrafast and robust spintronic devices. However, the lack of approaches to locally and deterministically manipulate their order parameter -- the Néel-vector -- remains a key limitation. Here, we introduce a fundamentally new paradigm in nanomagnetism, which we term lateral exchange bias (LEB), to achieve Néel vector control in bilayers of the vdW AF CrSBr. We exploit the single-crystalline registry formed by terraced CrSBr samples, where the bilayer Néel vector is controlled by LEB from neighboring, odd-layered flakes, whose nonzero magnetization we manipulate using magnetic fields. Using this control, we achieve nonvolatile manipulation of magnetic domains and domain walls (DWs) in AF CrSBr bilayers, establishing a powerful toolkit for controlling atomically thin AFs at the nanoscale. Our results challenge conventional views on exchange bias and provide a previously unexplored mechanism for achieving atomic-scale control of AFic order. Our findings pave the way for the development of advanced spintronic architectures and quantum technologies based on vdW magnets.

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BibTeXRIS

Clément Pellet-Mary, Debarghya Dutta, Märta A. Tschudin, Patrick Siegwolf, Boris Gross, David A. Broadway, Jordan Cox, Carolin Schrader, Jodok Happacher, Daniel G. Chica, Cory R. Dean, Xavier Roy, Patrick Maletinsky. 2025-08-20. Lateral Exchange Bias for Néel-Vector Control in Atomically Thin Antiferromagnets. https://arxiv.org/abs/2503.04922

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