• 文献标题:   Evidence for Flat Bands near the Fermi Level in Epitaxial Rhombohedral Multilayer Graphene
  • 文献类型:   Article
  • 作  者:   PIERUCCI D, SEDIRI H, HAJLAOUI M, GIRARD JC, BRUMME T, CALANDRA M, VELEZFORT E, PATRIARCHE G, SILLY MG, FERRO G, SOULIERE V, MARANGOLO M, SIROTTI F, MAURI F, OUERGHI A
  • 作者关键词:   rhombohedral multilayer graphene, flat band, density functional theory, angleresolved photoemission spectroscopy, stm/sts, stem
  • 出版物名称:   ACS NANO
  • ISSN:   1936-0851 EI 1936-086X
  • 通讯作者地址:   Univ Paris 06
  • 被引频次:   43
  • DOI:   10.1021/acsnano.5b01239
  • 出版年:   2015

▎ 摘  要

The stacking order of multilayer graphene has a profound influence on its electronic properties. In particular, it has been predicted that a rhombohedral stacking sequence displays a very flat conducting surface state: the longer the sequence, the flatter the band. In such a flat band, the role of electron electron correlation is enhanced, possibly resulting in high T-c superconductivity, magnetic order, or charge density wave order. Here we demonstrate that rhombohedral multilayers are easily obtained by epitaxial growth on 3C-S1C(111) on a 2 degrees off-axis 6H-SiC(0001). The resulting samples contain rhombohedral sequences of five layers on 70% of the surface. We confirm the presence of the flat band at the Fermi level by scanning tunneling spectroscopy and angle-resolved photoemission spectroscopy, in close agreement with the predictions of density functional theory calculations.