Giant Surface-driven Nonlinear Hall Effect in BiTeCl at Room Temperature

Zhihua Liu; Ziheng Wang; Yongbo Lv; Hanru Feng; Zhiwei Zhang; Bo Zhang; Feng Liu; Guohua Wang; Shengwei Jiang; Hao Chu; Hui Li; Dong Qian

arXiv · 2608.23368

Giant Surface-driven Nonlinear Hall Effect in BiTeCl at Room Temperature

Zhihua Liu·Ziheng Wang·Yongbo Lv·Hanru Feng·Zhiwei Zhang·Bo Zhang·Feng Liu·Guohua Wang·Shengwei Jiang·Hao Chu·Hui Li·Dong Qian

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Abstract

The nonlinear Hall effect (NLHE) provides a pathway to generate a Hall response in time-reversal-symmetric yet inversion-symmetry-broken systems. NLHE can rectify an alternating current into a transverse direct voltage, making it attractive for radio-frequency rectification, energy harvesting, and terahertz detection, applications for which device miniaturization remains a central pursuit. In this context, the inherent inversion symmetry breaking at surfaces is particularly appealing: because symmetry is necessarily broken at the surface of any crystal, irrespective of whether its bulk is centrosymmetric, surface-driven nonlinear responses lift the stringent constraint on bulk symmetry and open a route toward compact device architectures. Here we report the observation of a giant, surface-driven second-order nonlinear Hall effect in the Rashba-type polar semiconductor BiTeCl at room temperature. The determined second-order nonlinear Hall susceptibility at 300 K reaches 1.68 $μ$mV$^{-1}$, which is 80 times larger than that of the best previously reported surface-dominated systems. We attribute this giant response to the synergistic interplay between BiTeCl's polar crystal structure and its rich surface states: the polar stacking renders the top and bottom surfaces inequivalent, so that the nonlinear response originates from a single surface without compensation from the other. Symmetry and scaling analyses suggest that both skew-scattering and side-jump mechanisms contribute to the observed effect. Our findings not only identify BiTeCl as a promising platform for future applications utilizing the NLHE, but also establish the asymmetry between the opposite surfaces of a polar crystal as a general design principle for discovering surface-driven materials with larger nonlinear Hall responses.

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Zhihua Liu, Ziheng Wang, Yongbo Lv, Hanru Feng, Zhiwei Zhang, Bo Zhang, Feng Liu, Guohua Wang, Shengwei Jiang, Hao Chu, Hui Li, Dong Qian. 2026-08-24. Giant Surface-driven Nonlinear Hall Effect in BiTeCl at Room Temperature. https://arxiv.org/abs/2608.23368

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