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Chiral-Bubble-Induced Topological Hall Effect in Ferromagnetic Topological Insulator Heterostructures.

ABSTRACT: We report compelling evidence of an emergent topological Hall effect (THE) from chiral bubbles in a two-dimensional uniaxial ferromagnet, V-doped Sb₂Te₃ heterostructure. The sign of THE signal is determined by the net curvature of domain walls in different domain configurations, and the strength of THE signal is correlated with the density of nucleation or pinned bubble domains. The experimental results are in good agreement with the integrated linear transport and Monte Carlo simulations, corroborating the emergent gauge field at chiral magnetic bubbles. Our findings not only reveal a general mechanism of THE in two-dimensional ferromagnets but also pave the way for the creation and manipulation of topological spin textures for spintronic applications.

SUBMITTER: Wang W

PROVIDER: S-EPMC8276525 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Chiral-Bubble-Induced Topological Hall Effect in Ferromagnetic Topological Insulator Heterostructures.

Wang Wenbo W Zhao Yi-Fan YF Wang Fei F Daniels Matthew W MW Chang Cui-Zu CZ Zang Jiadong J Xiao Di D Wu Weida W

Nano letters 20210106 2

We report compelling evidence of an emergent topological Hall effect (THE) from chiral bubbles in a two-dimensional uniaxial ferromagnet, V-doped Sb<sub>2</sub>Te<sub>3</sub> heterostructure. The sign of THE signal is determined by the net curvature of domain walls in different domain configurations, and the strength of THE signal is correlated with the density of nucleation or pinned bubble domains. The experimental results are in good agreement with the integrated linear transport and Monte Ca ...[more]

PMID: 33404255

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