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arXiv · 2610.05713

Gate-tunable large second-order and third-order nonlinear Hall effect in topological insulator BiSbTeSe2

Fengyi Guo·Shuai Zhang·Xiubing Li·Zheng Dai·Congcong Li·Yufan Ju·Ziqi Wang·Cheng Bin·Zhe Ying·Fengqi Song
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Abstract

The nonlinear Hall effect (NLHE) holds significant promise for next-generation electronic device applications, and it is essential to explore and engineer a strong and highly tunable NLHE. In this work, we report large second-order and third-order NLHEs in dual-gated BiSbTeSe2 devices. Both the second-order and third-order NLHE are highly gate-tunable. The second-order NLHE exhibits a higher generation efficiency than those reported in previous topological insulator systems, and it can be stably observed up to room temperature. Meanwhile, the generation efficiency of the third-order NLHE is comparable to previously reported values. The scaling analysis indicates that the second-order NLHE is consistent with contributions from skew scattering and a term compatible with either the Berry curvature dipole or side jump, whereas the third-order NLHE is consistent with contributions from the Berry connection polarizability tensor and higher-order skew scattering. Our work establishes a promising experimental platform for the development of NLHE-based devices.

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Fengyi Guo, Shuai Zhang, Xiubing Li, Zheng Dai, Congcong Li, Yufan Ju, Ziqi Wang, Cheng Bin, Zhe Ying, Fengqi Song. 2026-10-05. Gate-tunable large second-order and third-order nonlinear Hall effect in topological insulator BiSbTeSe2. https://doi.org/10.1103/y55k-pvgq

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