Single-layer Skyrmions in a van der Waals Antiferromagnet

Alessio Pozzi; Maxim Mostovoy

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arXiv · 2111.11420

Single-layer Skyrmions in a van der Waals Antiferromagnet

Alessio Pozzi·Maxim Mostovoy

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Abstract

Transition metal halides are quasi-two-dimensional van der Waals magnets that can potentially host antiferromagnetic (AFM) skyrmions induced by competing exchange interactions. We study theoretically magnetic states of Fe-doped NiBr$_2$ using spin interactions obtained by fitting experimental data. We find that AFM interlayer interactions suppress skyrmion lattices but allow for skyrmions with topological charges $1,2$ and $3$ confined to a single magnetic layer. These single-layer skyrmions exist in three different magnetic phases and their dynamics changes drastically at the transition from a uniform to a non-collinear modulated state.

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Alessio Pozzi, Maxim Mostovoy. 2021-11-22. Single-layer Skyrmions in a van der Waals Antiferromagnet. https://arxiv.org/abs/2111.11420

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