• 文献标题:   Magnetotransport Properties of Quasi-Free-Standing Epitaxial Graphene Bilayer on SiC: Evidence for Bernal Stacking
  • 文献类型:   Article
  • 作  者:   LEE K, KIM S, POINTS MS, BEECHEM TE, OHTA T, TUTUC E
  • 作者关键词:   graphene, bilayer, sic, quantum hall, bernal stacking
  • 出版物名称:   NANO LETTERS
  • ISSN:   1530-6984 EI 1530-6992
  • 通讯作者地址:   Univ Texas Austin
  • 被引频次:   29
  • DOI:   10.1021/nl201430a
  • 出版年:   2011

▎ 摘  要

We investigate the magnetotransport properties of quasi-free-standing epitaxial graphene bilayer on SiC, grown by atmospheric pressure graphitization in Ar, followed by H-2 intercalation. At the charge neutrality point, the longitudinal resistance shows an insulating behavior, which follows a temperature dependence consistent with variable range hopping transport in a gapped state. In a perpendicular magnetic field, we observe quantum Hall states (QHSs) both at filling factors (v) multiples of four (v = 4, 8, 12), as well as broken valley symmetry QHSs at v = 0 and v = 6. These results unambiguously show that the quasi-free-standing graphene bilayer grown on the Si-face of SiC exhibits Bernal stacking.