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arXiv · 2306.10116

Topological Flat Bands in Graphene Super-moir\'e Lattices

Mohammed M. Al Ezzi·Junxiong Hu·Ariando·Francisco Guinea·Shaffique Adam
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Abstract

Moir\'e-pattern based potential engineering has become an important way to explore exotic physics in a variety of two-dimensional condensed matter systems. While these potentials have induced correlated phenomena in almost all commonly studied 2D materials, monolayer graphene has remained an exception. We demonstrate theoretically that a single layer of graphene, when placed between two bulk boron nitride crystal substrates with the appropriate twist angles can support a robust topological ultra-flat band emerging from the second hole band. This is one of the simplest platforms to design and exploit topological flat bands.

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Mohammed M. Al Ezzi, Junxiong Hu, Ariando, Francisco Guinea, Shaffique Adam. 2023-06-16. Topological Flat Bands in Graphene Super-moir\'e Lattices. https://doi.org/10.1103/physrevlett.132.126401

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