Abstract
The unoccupied and occupied σ and π bands of graphene on Pt(111) were measured using near-edge x-ray absorption spectroscopy (XAS) and resonant inelastic x-ray scattering (RIXS) at the carbon edge. Elemental specificity and crystal-momentum conservation allows for detection of the dispersive band structure. In addition to features arising from the band structure of free-standing graphene, signatures of symmetry breaking were identified in XAS and in RIXS for excitation around the Fermi level. These additional features are proposed to derive from weak graphene-substrate interactions which manifest as substrate hybridization and surface umklapp processes due to Moiré superlattice vectors.
- Received 30 November 2011
DOI:https://doi.org/10.1103/PhysRevB.85.045419
©2012 American Physical Society