Metamagnetism of weakly-coupled antiferromagnetic topological insulators

Méta-magnétisme d'isolants topologiques 3D magnétiques faiblement couplés

Aoyu Tan (1, 2) , Valentin Labracherie (2, 1) , Narayan Kunchur (2) , Anja U B Wolter (2) , Joaquin Cornejo (2) , Joseph Dufouleur (2) , Bernd Büchner (2) , Anna Isaeva (2) , Romain Giraud (1, 2)

1 SPINTEC - SPINtronique et TEchnologie des Composants
2 IFW Dresden - Leibniz Institute for Solid State and Materials Research

The magnetic properties of the van der Waals magnetic topological insulators MnBi2Te4 and MnBi4Te7 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.

Domaines: Systèmes mésoscopiques et effet Hall quantique [cond-mat.mes-hall]; Science des matériaux [cond-mat.mtrl-sci]

Aoyu Tan, Valentin Labracherie, Narayan Kunchur, Anja U B Wolter, Joaquin Cornejo, et al.. Metamagnetism of weakly-coupled antiferromagnetic topological insulators. Physical Review Letters, 2020, 124 (197201). ⟨hal-02457539⟩