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arXiv · 2305.14423

Chiral model of twisted bilayer graphene realized in a monolayer

Valentin Crépel·Aaron Dunbrack·Daniele Guerci·John Bonini·Jennifer Cano
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Abstract

We demonstrate that a single layer of graphene subject to a superlattice potential nearly commensurate to a $\sqrt{3} \times \sqrt{3}$ supercell exactly maps to the chiral model of twisted bilayer graphene, albeit with half as many degrees of freedom. We comprehensively review the properties of this ``half-chiral model,'' including the interacting phases stabilized at integer fillings and the effects of substrate-induced symmetry breaking. We list candidate substrates that could produce a superlattice potential on graphene with the correct periodicity to access the flat band limit. Experimental measurements on a half-chiral moire heterostructure, in which valley-skyrmions cannot form, could yield insights on the physics they mediate in twisted bilayer graphene.

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Valentin Crépel, Aaron Dunbrack, Daniele Guerci, John Bonini, Jennifer Cano. 2023-05-23. Chiral model of twisted bilayer graphene realized in a monolayer. https://doi.org/10.1103/physrevb.108.075126

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