Fractional Chern insulators in magic-angle twisted bilayer graphene.

ABSTRACT: Fractional Chern insulators (FCIs) are lattice analogues of fractional quantum Hall states that may provide a new avenue towards manipulating non-Abelian excitations. Early theoretical studies^1-7 have predicted their existence in systems with flat Chern bands and highlighted the critical role of a particular quantum geometry. However, FCI states have been observed only in Bernal-stacked bilayer graphene (BLG) aligned with hexagonal boron nitride (hBN)⁸, in which a very large magnetic field is responsible for the existence of the Chern bands, precluding the realization of FCIs at zero field. By contrast, magic-angle twisted BLG^9-12 supports flat Chern bands at zero magnetic field^13-17, and therefore offers a promising route towards stabilizing zer

SUBMITTER: Xie Y 

PROVIDER: S-EPMC8674130 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature