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arXiv · 1905.04839

Experimental observation of the gate-controlled reversal of the anomalous Hall effect in the intrinsic magnetic topological insulator MnBi2Te4 device

Shuai Zhang·Rui Wang·Xuepeng Wang·Boyuan Wei·Huaiqiang Wang·Gang Shi·Feng Wang·Bin Jia·Yiping Ouyang·Bo Chen·Qianqian Liu·Faji Xie·Fucong Fei·Minhao Zhang·Xuefeng Wang·Di Wu·Xiangang Wan·Fengqi Song·Haijun Zhang·Baigeng Wang
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Abstract

Here we report the reserved anomalous Hall effect (AHE) in the 5-septuple-layer van der Waals device of the intrinsic magnetic topological insulator MnBi2Te4. By employing the top/bottom gate, a negative AHE loop gradually decreases to zero and changes to a reversed sign. The reversed AHE exhibits distinct coercive fields and temperature dependence from the previous AHE. It reaches the maximum inside the gap of the Dirac cone. The newly-seen reversed AHE is attributed to the competition of the intrinsic Berry curvature and the Dirac-gap enhanced extrinsic skew scattering. Its gate-controlled switching contributes a scheme for the topological spin field-effect transistors.

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Shuai Zhang, Rui Wang, Xuepeng Wang, Boyuan Wei, Huaiqiang Wang, Gang Shi, Feng Wang, Bin Jia, Yiping Ouyang, Bo Chen, Qianqian Liu, Faji Xie, Fucong Fei, Minhao Zhang, Xuefeng Wang, Di Wu, Xiangang Wan, Fengqi Song, Haijun Zhang, Baigeng Wang. 2019-05-13. Experimental observation of the gate-controlled reversal of the anomalous Hall effect in the intrinsic magnetic topological insulator MnBi2Te4 device. https://doi.org/10.1021/acs.nanolett.9b04555

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