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arXiv · 2507.12254

Heavy fermion phase diagram in magic-angle twisted trilayer graphene

Le Zhang·Wenqiang Zhou·Xinjie Fang·Zhen Zhan·Kenji Watanabe·Takashi Taniguchi·Yi-feng Yang·Shuigang Xu
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Abstract

The interplay between localized magnetic moments and itinerant electrons gives rise to exotic quantum states in condensed matter systems. Here, we demonstrate an electrically tunable heavy fermion phase diagram in magic-angle twisted trilayer graphene, achieved by controlling the Kondo hybridization between localized flat-band electrons and itinerant Dirac electrons via a displacement field. Our results reveal a continuous quantum phase transition from an antiferromagnetic semimetal to a paramagnetic heavy fermion metal. At quantum critical point, we observe effective mass divergence and Fermi surface reconstruction. This highly tunable platform offers unprecedented control over heavy fermion physics, establishing moire heterostructures as a versatile arena for exploring correlated quantum phases-including potential unconventional superconductivity-in two-dimensional limit.

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Le Zhang, Wenqiang Zhou, Xinjie Fang, Zhen Zhan, Kenji Watanabe, Takashi Taniguchi, Yi-feng Yang, Shuigang Xu. 2025-07-16. Heavy fermion phase diagram in magic-angle twisted trilayer graphene. https://doi.org/10.1103/zzks-vkl2

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