• 文献标题:   Unusual magnetotransport in twisted bilayer graphene
  • 文献类型:   Article
  • 作  者:   FINNEY J, SHARPE AL, FOX EJ, HSUEH CL, PARKER DE, YANKOWITZ M, CHEN SW, WATANABE K, TANIGUCHI T, DEAN CR, VISHWANATH A, KASTNER MA, GOLDHABERGORDON D
  • 作者关键词:   hofstadter s butterfly, twisted bilayer graphene, anisotropy
  • 出版物名称:   PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
  • ISSN:   0027-8424 EI 1091-6490
  • 通讯作者地址:  
  • 被引频次:   4
  • DOI:   10.1073/pnas.2118482119
  • 出版年:   2022

▎ 摘  要

We present transport measurements of bilayer graphene with a 1.38 degrees interlayer twist. As with other devices with twist angles substantially larger than the magic angle of 1.1 degrees, we do not observe correlated insulating states or band reorganization. However, we do observe several highly unusual behaviors in magnetotransport. For a large range of densities around half filling of the moire bands, magnetoresistance is large and quadratic. Over these same densities, the magnetoresistance minima corresponding to gaps between Landau levels split and bend as a function of density and field. We reproduce the same splitting and bending behavior in a simple tight-binding model of Hofstadter's butterfly on a triangular lattice with anisotropic hopping terms. These features appear to be a generic class of experimental manifestations of Hofstadter's butterfly and may provide insight into the emergent states of twisted bilayer graphene.