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arXiv · 1709.08161

Dimensional Crossover Induced Topological Hall Effect in a Magnetic Topological Insulator

Chang Liu·Yunyi Zang·Wei Ruan·Yan Gong·Ke He·Xucun Ma·Qi-Kun Xue·Yayu Wang
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Abstract

We report transport studies of Mn-doped Bi2Te3 topological insulator (TI) films with accurately controlled thickness grown by molecular beam epitaxy. We find that films thicker than 5 quintuple-layer (QL) exhibit the usual anomalous Hall effect for magnetic TIs. When the thickness is reduced to 4 QL, however, characteristic features associated with the topological Hall effect (THE) emerge. More surprisingly, the THE vanishes again when the film thickness is further reduced to 3 QL. Theoretical calculations demonstrate that the coupling between the top and bottom surface states at the dimensional crossover regime stabilizes the magnetic skyrmion structure that is responsible for the THE.

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Chang Liu, Yunyi Zang, Wei Ruan, Yan Gong, Ke He, Xucun Ma, Qi-Kun Xue, Yayu Wang. 2017-09-24. Dimensional Crossover Induced Topological Hall Effect in a Magnetic Topological Insulator. https://doi.org/10.1103/physrevlett.119.176809

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