• 文献标题:   Topological Bloch bands in graphene superlattices
  • 文献类型:   Article
  • 作  者:   SONG JCW, SAMUTPRAPHOOT P, LEVITOV LS
  • 作者关键词:   topological band, graphene, van der waals heterostructure
  • 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:   CALTECH
  • 被引频次:   29
  • DOI:   10.1073/pnas.1424760112
  • 出版年:   2015

▎ 摘  要

We outline a designer approach to endow widely available plain materials with topological properties by stacking them atop other nontopological materials. The approach is illustrated with a model system comprising graphene stacked atop hexagonal boron nitride. In this case, the Berry curvature of the electron Bloch bands is highly sensitive to the stacking configuration. As a result, electron topology can be controlled by crystal axes alignment, granting a practical route to designer topological materials. Berry curvature manifests itself in transport via the valley Hall effect and long-range chargeless valley currents. The nonlocal electrical response mediated by such currents provides diagnostics for band topology.