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arXiv · 2212.10685

Lattice Model For The Quantum Anomalous Hall Effect in Moiré Graphene

Ahmed Khalifa·Ganpathy Murthy·Ribhu K. Kaul
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Abstract

Inspired by experiments on magic angle twisted bilayer graphene, we present a lattice mean-field model for the quantum anomalous Hall effect in a moiré setting. Our hopping model thus provides a simple route to a moiré Chern insulator in commensurately twisted models. We present a study of our model in the ribbon geometry, in which we demonstrate the presence of thick chiral edge states that have a transverse localization that scales with the moiré lattice spacing. We also study the electronic structure of a domain wall between opposite Chern insulators. Our model and results are relevant to experiments that will image or manipulate the moiré quantum anomalous Hall edge states.

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Ahmed Khalifa, Ganpathy Murthy, Ribhu K. Kaul. 2022-12-20. Lattice Model For The Quantum Anomalous Hall Effect in Moiré Graphene. https://doi.org/10.1103/physrevb.107.235137

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