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Exchange-biasing topological charges by antiferromagnetism.

ABSTRACT: Geometric Hall effect is induced by the emergent gauge field experienced by the carriers adiabatically passing through certain real-space topological spin textures, which is a probe to non-trivial spin textures, such as magnetic skyrmions. We report experimental indications of spin-texture topological charges induced in heterostructures of a topological insulator (Bi,Sb)₂Te₃ coupled to an antiferromagnet MnTe. Through a seeding effect, the pinned spins at the interface leads to a tunable modification of the averaged real-space topological charge. This effect experimentally manifests as a modification of the field-dependent geometric Hall effect when the system is field-cooled along different directions. This heterostructure represents a platform for manipulating magnetic topological transitions using antiferromagnetic order.

SUBMITTER: He QL

PROVIDER: S-EPMC6050290 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Exchange-biasing topological charges by antiferromagnetism.

He Qing Lin QL Yin Gen G Grutter Alexander J AJ Pan Lei L Che Xiaoyu X Yu Guoqiang G Gilbert Dustin A DA Disseler Steven M SM Liu Yizhou Y Shafer Padraic P Zhang Bin B Wu Yingying Y Kirby Brian J BJ Arenholz Elke E Lake Roger K RK Han Xiaodong X Wang Kang L KL

Nature communications 20180717 1

Geometric Hall effect is induced by the emergent gauge field experienced by the carriers adiabatically passing through certain real-space topological spin textures, which is a probe to non-trivial spin textures, such as magnetic skyrmions. We report experimental indications of spin-texture topological charges induced in heterostructures of a topological insulator (Bi,Sb)<sub>2</sub>Te<sub>3</sub> coupled to an antiferromagnet MnTe. Through a seeding effect, the pinned spins at the interface lead ...[more]

PMID: 30018306

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