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arXiv · 1912.13113

Meta-magnetism of weakly-coupled antiferromagnetic topological insulators

Aoyu Tan·Valentin Labracherie·Narayan Kunchur·Anja U. B. Wolter·Joaquin Cornejo·Joseph Dufouleur·Bernd Büchner·Anna Isaeva·Romain Giraud
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Abstract

The magnetic properties of the van der Waals magnetic topological insulators MnBi$_2$Te$_4$ and MnBi$_4$Te$_7$ are investigated by magneto-transport measurements. We evidence that the relative strength of the inter-layer exchange coupling J to the uniaxial anisotropy K controls a transition from an A-type antiferromagnetic order to a ferromagnetic-like metamagnetic state. A bi-layer Stoner-Wohlfarth model allows us to describe this evolution, as well as the typical angular dependence of specific signatures, such as the spin-flop transition of the uniaxial antiferromagnet and the switching field of the metamagnet.

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Aoyu Tan, Valentin Labracherie, Narayan Kunchur, Anja U. B. Wolter, Joaquin Cornejo, Joseph Dufouleur, Bernd Büchner, Anna Isaeva, Romain Giraud. 2020-01-09. Meta-magnetism of weakly-coupled antiferromagnetic topological insulators. https://doi.org/10.1103/physrevlett.124.197201

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