Mathematics of magic angles in a model of twisted bilayer graphene

• URL: http://arxiv.org/abs/2008.08489v4
• Date: Mon, 17 May 2021 09:43:52 GMT
• Title: Mathematics of magic angles in a model of twisted bilayer graphene
• Authors: Simon Becker, Mark Embree, Jens Wittsten, Maciej Zworski
• Abstract summary: We provide a mathematical account of the recent Physical Reviews Letter by Tarnopolsky--Kruchkov--Vishwanath. New contributions are a spectral characterization of magic angles, its accurate numerical implementation and an exponential estimate on the squeezing of all bands as the angle decreases.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We provide a mathematical account of the recent Physical Reviews Letter by Tarnopolsky--Kruchkov--Vishwanath. The new contributions are a spectral characterization of magic angles, its accurate numerical implementation and an exponential estimate on the squeezing of all bands as the angle decreases. Pseudospectral phenomena due to the non-hermitian nature of operators appearing in the model play a crucial role in our analysis.

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