Programmable Quantum Anomalous Hall Insulator in Twisted Crystalline Flatbands

Wenxuan Wang; Yijie Wang; Zaizhe Zhang; Zihao Huo; Gengdong Zhou; Kenji Watanabe; Takashi Taniguchi; X. C. Xie; Kaihui Liu; Zhida Song; Xiaobo Lu

arXiv · 2507.10875

Programmable Quantum Anomalous Hall Insulator in Twisted Crystalline Flatbands

Wenxuan Wang·Yijie Wang·Zaizhe Zhang·Zihao Huo·Gengdong Zhou·Kenji Watanabe·Takashi Taniguchi·X. C. Xie·Kaihui Liu·Zhida Song·Xiaobo Lu

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Abstract

The isospin flavors in condensed matters can be continuously broken, forming various symmetry-broken quantum states. In moir\'e crystals, the competition between different isospin configurations can be effectively tuned by the twist angles and staciking orders. Here we report twisted double rhombohedral-trilayer-gaphene as a new twisted crystalline flatbands system showing rich moir\'e dependent topological phenomena. In devices with small twist angles, programmable Chern insulators with Chern number C = 3 at integer moir\'e filling v = 1 have been observed. We have further revealed an exotic hidden order which can quench the Chern insulator as well as multiple first-order transitions between different symmetry-broken phases. Interestly, in the device with a slightly larger twist angle, multiple Chern insulators with C = 1 at fractional moir\'e fillings including v = 1/4, 1/3 and 1/2 have been observed, whereas the Chern insulator at v = 1 is abscent. Our study demonstrated the twisted flatbands form rhombohedral-multilayer-graphene as a new platform to study tunable high Chern insulators as well as new devices for quantum storage and computation.

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Wenxuan Wang, Yijie Wang, Zaizhe Zhang, Zihao Huo, Gengdong Zhou, Kenji Watanabe, Takashi Taniguchi, X. C. Xie, Kaihui Liu, Zhida Song, Xiaobo Lu. 2025-07-15. Programmable Quantum Anomalous Hall Insulator in Twisted Crystalline Flatbands. https://arxiv.org/abs/2507.10875

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