• 文献标题:   Incommensurability-induced sub-ballistic narrow-band-states in twisted bilayer graphene
  • 文献类型:   Article
  • 作  者:   GONCALVES M, OLYAEI HZ, AMORIM B, MONDAINI R, RIBEIRO P, CASTRO EV
  • 作者关键词:   moire system, quasiperiodicity, twisted bilayer graphene, incommensurate system
  • 出版物名称:   2D MATERIALS
  • ISSN:   2053-1583
  • 通讯作者地址:  
  • 被引频次:   4
  • DOI:   10.1088/2053-1583/ac3259
  • 出版年:   2022

▎ 摘  要

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 of samples with fixed width decreases with the system size in the longitudinal direction for incommensurate angles within the sub-ballistic regime. Our results show that incommensurability/quasiperiodicity 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.