• 文献标题:   Electrostatic effects, band distortions, and superconductivity in twisted graphene bilayers
  • 文献类型:   Article
  • 作  者:   GUINEA F, WALET NR
  • 作者关键词:   graphene, bilayer, superconductivity, twisted
  • 出版物名称:   PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
  • ISSN:   0027-8424
  • 通讯作者地址:   Imdea Nanosci
  • 被引频次:   32
  • DOI:   10.1073/pnas.1810947115
  • 出版年:   2018

▎ 摘  要

Bilayer graphene twisted by a small angle shows a significant charge modulation away from neutrality, as the charge in the narrow bands near the Dirac point is mostly localized in a fraction of the Moire unit cell. The resulting electrostatic potential leads to a filling-dependent change in the low-energy bands, of a magnitude comparable to or larger than the bandwidth. These modifications can be expressed in terms of new electron-electron interactions, which, when expressed in a local basis, describe electron-assisted hopping terms. These interactions favor superconductivity at certain fillings.