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arXiv · 2103.05821

Mapping the phase diagram of the quantum anomalous Hall and topological Hall effects in a dual-gated magnetic topological insulator heterostructure

Run Xiao·Di Xiao·Jue Jiang·Jae-Ho Shin·Fei Wang·Yi-Fan Zhao·Ruo-Xi Zhang·Anthony Richardella·Ke Wang·Morteza Kayyalha·Moses H. W. Chan·Chao-Xing Liu·Cui-Zu Chang·Nitin Samarth
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Abstract

We use magnetotransport in dual-gated magnetic topological insulator heterostructures to map out a phase diagram of the topological Hall and quantum anomalous Hall effects as a function of the chemical potential (primarily determined by the back gate voltage) and the asymmetric potential (primarily determined by the top gate voltage). A theoretical model that includes both surface states and valence band quantum well states allows the evaluation of the variation of the Dzyaloshinskii-Moriya interaction and carrier density with gate voltages. The qualitative agreement between experiment and theory provides strong evidence for the existence of a topological Hall effect in the system studied, opening up a new route for understanding and manipulating chiral magnetic spin textures in real space.

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Run Xiao, Di Xiao, Jue Jiang, Jae-Ho Shin, Fei Wang, Yi-Fan Zhao, Ruo-Xi Zhang, Anthony Richardella, Ke Wang, Morteza Kayyalha, Moses H. W. Chan, Chao-Xing Liu, Cui-Zu Chang, Nitin Samarth. 2021-03-10. Mapping the phase diagram of the quantum anomalous Hall and topological Hall effects in a dual-gated magnetic topological insulator heterostructure. https://doi.org/10.1103/physrevresearch.3.l032004

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