Diverse high-Chern-number quantum anomalous Hall insulators in twisted rhombohedral graphene

Naitian Liu; Zhangyuan Chen; Jing Ding; Wenqiang Zhou; Hanxiao Xiang; Xinjie Fang; Linfeng Wu; Xiaowan Zhan; Le Zhang; Qianmei Chen; Kenji Watanabe; Takashi Taniguchi; Na Xin; Shuigang Xu

arXiv · 2507.11347

Diverse high-Chern-number quantum anomalous Hall insulators in twisted rhombohedral graphene

Naitian Liu·Zhangyuan Chen·Jing Ding·Wenqiang Zhou·Hanxiao Xiang·Xinjie Fang·Linfeng Wu·Xiaowan Zhan·Le Zhang·Qianmei Chen·Kenji Watanabe·Takashi Taniguchi·Na Xin·Shuigang Xu

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Abstract

Quantum anomalous Hall (QAH) insulators with high Chern number (C) enables multiple dissipationless edge channels for low-power-consumption electronics. We report the realization of multiple high-C QAH insulators including C=3,5,6, and 7 in twisted monolayer-rhombohedral pentalayer graphene. In twist angles of approximately 1.40{\deg}, we observe QAH effect with C=5 at a filling of one electron per moir\'e unit cell, persisting up to 2 Kelvin. Furthermore, incommensurate QAH insulators with C=5,6, and 7 emerge at partial fillings. In twist angles of 0.89{\deg}, Chern insulators with C=3 and C=6 appear at fillings of two and three electrons, respectively. Our findings establish twisted rhombohedral multilayer graphene as a highly tunable platform for multichannel, dissipationless electronics and for the exploration of exotic quantum Hall states beyond traditional Landau level paradigm.

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Naitian Liu, Zhangyuan Chen, Jing Ding, Wenqiang Zhou, Hanxiao Xiang, Xinjie Fang, Linfeng Wu, Xiaowan Zhan, Le Zhang, Qianmei Chen, Kenji Watanabe, Takashi Taniguchi, Na Xin, Shuigang Xu. 2025-07-15. Diverse high-Chern-number quantum anomalous Hall insulators in twisted rhombohedral graphene. https://arxiv.org/abs/2507.11347

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