Origin of the π -band replicas in the electronic structure of graphene grown on 4H -SiC(0001)

Research output: Contribution to journalArticle

Abstract

The calculated electronic band structure of graphene is relatively simple, with a Fermi surface consisting only of six Dirac cones in the first Brillouin zone - one at each K̄. In contrast, angle-resolved photoemission measurements of graphene grown on SiC(0001) often show six satellite Dirac cones surrounding each primary Dirac cone. Recent studies have reported two further Dirac cones along the Γ-K̄ line, and argue that these are not photoelectron diffraction artifacts but real bands deriving from a modulation of the ionic potential in the graphene layer. Here we present measurements using linearly polarized synchrotron light which show all of these replicas as well as several additional ones. Using information obtained from dark corridor orientations and angular warping, we demonstrate that all but one of these additional features - including those previously assigned as real initial-state bands - are possible to explain by simple final-state photoelectron diffraction.

Details

Authors
Organisations
External organisations
  • Chalmers University of Technology
  • Linköping University
  • University of Luxembourg
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Condensed Matter Physics
Original languageEnglish
Article number115404
JournalPhysical Review B
Volume99
Issue number11
Publication statusPublished - 2019
Publication categoryResearch
Peer-reviewedYes