• 文献标题:   Dirac edges of fractal magnetic minibands in graphene with hexagonal moire superlattices
  • 文献类型:   Article
  • 作  者:   CHEN X, WALLBANK JR, PATEL AA, MUCHAKRUCZYNSKI M, MCCANN E, FAL KO VI
  • 作者关键词:  
  • 出版物名称:   PHYSICAL REVIEW B
  • ISSN:   2469-9950 EI 2469-9969
  • 通讯作者地址:   Univ Lancaster
  • 被引频次:   28
  • DOI:   10.1103/PhysRevB.89.075401
  • 出版年:   2014

▎ 摘  要

We find a systematic reappearance of massive Dirac features at the edges of consecutive minibands formed at magnetic fields B-p/q = p/q phi(0)/S providing rational magnetic flux through a unit cell of the moire superlattice created by a hexagonal substrate for electrons in graphene. The Dirac-type features in the minibands at B = B-p/q determine a hierarchy of gaps in the surrounding fractal spectrum and show that these minibands have topological insulator properties. Using the additional q-fold degeneracy of magnetic minibands at B-p/q, we trace the hierarchy of the gaps to their manifestation in the form of incompressible states upon variation of the carrier density and magnetic field.