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arXiv · 2008.07542

Incommensurability-induced sub-ballistic narrow-band-states in twisted bilayer graphene

Miguel Gonçalves·Hadi Z. Olyaei·Bruno Amorim·Rubem Mondaini·Pedro Ribeiro·Eduardo V. Castro
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Abstract

We study the localization properties of electrons in incommensurate twisted bilayer graphene for small angles, encompassing the narrow-band regime, by numerically exact means. Sub-ballistic states are found within the narrow-band region around the magic angle. Such states are delocalized in momentum-space and follow non-Poissonian level statistics, in contrast with their ballistic counterparts found for close commensurate angles. Transport results corroborate this picture: for large enough systems, the conductance decreases with system size for incommensurate angles within the sub-ballistic regime. Our results show that incommensurability effects are of crucial importance in the narrow-band regime. The incommensurate nature of a general twist angle must therefore be taken into account for an accurate description of magic-angle twisted bilayer graphene.

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Miguel Gonçalves, Hadi Z. Olyaei, Bruno Amorim, Rubem Mondaini, Pedro Ribeiro, Eduardo V. Castro. 2020-08-17. Incommensurability-induced sub-ballistic narrow-band-states in twisted bilayer graphene. https://doi.org/10.1088/2053-1583%2Fac3259

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