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arXiv · 2303.00103

Flat Bands and High Chern Numbers in Twisted Multilayer Graphene

Mengxuan Yang
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Abstract

Motivated by recent Physical Review Letters of Wang-Liu and Ledwith-Vishwanath-Khalaf, we study Tarnopolsky-Kruchkov-Vishwanath chiral model of two sheets of $n$-layer Bernal stacked graphene twisted by a small angle using the framework developed by Becker-Embree-Wittsten-Zworski. We show that magic angles of this model are exactly the same as magic angles of chiral twisted bilayer graphene with multiplicity. For small inter-layer tunneling potentials, we compute the band separation at Dirac points as we turning on the tunneling parameter. Flat band eigenfunctions are also constructed using a new theta function argument and this yields a complex line bundle with the Chern number $-n$.

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Mengxuan Yang. 2023-02-28. Flat Bands and High Chern Numbers in Twisted Multilayer Graphene. https://doi.org/10.1063/5.0153987

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