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arXiv · 2606.03497

Ferroelectric-tunable quantum nonlinearity of chiral Bloch electrons in a moir\'e system

Zitian Pan·Jundong Zhu·Yu Hong·Jingwei Dong·Dongxia Shi·Kenji Watanabe·Takashi Taniguchi·Luojun Du·Wei Yang·Guangyu Zhang
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Abstract

Sliding ferroelectricity in van der Waals materials shows great potential for designing robust memory devices. However, its thermodynamic behaviors and the coupling with certain quantum effects remain largely unexplored. Here, we demonstrate ferroelectric control over quantum nonlinear transport in a hexagonal boron nitride (hBN) encapsulated twisted double-bilayer graphene moir\'e heterostructure. The ferroelectricity is attributed to the presence of rhombohedral stacking in the top hBN, confirmed by both electrical transport and optical second harmonic generation (SHG) measurements. Remarkably, the polarization magnitude remains temperature-independent across 1.7-200 K, while nucleation time exhibits thermally activated behavior, decreasing with increasing temperature. Furthermore, we demonstrate a ferroelectric-switchable nonlinear Hall effect, attributed to the chiral scattering induced by Berry curvature, with outstanding fatigue-resistant and nonvolatility, demonstrating direct coupling between sliding ferroelectricity and quantum geometric properties. Our results establish sliding ferroelectrics as a platform for exploring electrically programmable Berry curvature physics.

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Zitian Pan, Jundong Zhu, Yu Hong, Jingwei Dong, Dongxia Shi, Kenji Watanabe, Takashi Taniguchi, Luojun Du, Wei Yang, Guangyu Zhang. 2026-06-02. Ferroelectric-tunable quantum nonlinearity of chiral Bloch electrons in a moir\'e system. https://doi.org/10.1021/acs.nanolett.6c01622

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