Flat Bands and High Chern Numbers in Twisted Multilayer Graphene

• URL: http://arxiv.org/abs/2303.00103v1
• Date: Tue, 28 Feb 2023 22:04:15 GMT
• Title: Flat Bands and High Chern Numbers in Twisted Multilayer Graphene
• Authors: Mengxuan Yang
• Abstract summary: We study Tarnopolsky-Kruchkov-Vishwanath chiral model of two sheets of $n$-layer Bernal stacked graphene twisted by a small angle. We show that magic angles of this model are exactly the same as magic angles of chiral twisted bilayer graphene with multiplicity.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• 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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