Analysis of atomic Moiré patterns on graphene/Rh(1 1 1)

• Published in: Surface science 2018-02, Vol.668, p.107-111
• Main Authors: Holtsch, Anne, Euwens, Tobias, Uder, Bernd, Grandthyll, Samuel, Müller, Frank, Hartmann, Uwe
• Format: Article
• Language: English
• Subjects: Corrugated sheet; Graphene; Hybridization; Low energy electron diffraction; Microscopy; Moire patterns; Moiré patterns; Scanning tunneling microscopy; Scanning tunneling spectroscopy; Spectrum analysis; Substrates; Symmetry; X-ray photoelectron spectroscopy
• ISSN: 0039-6028; 1879-2758
• DOI: 10.1016/j.susc.2017.10.026

•Moiré pattern of graphene/Rh(1 1 1) show a buckling of the graphene sheet in scanning tunneling microscopy.•Moiré pattern of graphene/Rh(1 1 1) with different lattice constant is observed.•Scanning tunneling spectroscopy of Moiré pattern shows hybridization between graphene and Rh(1 1 1). In scanning tunneling microscopy the lattice mismatch between graphene and Rh(1 1 1) is observed as an additional superstructure. This superstructure is called Moiré pattern. Various symmetry sites occur in a Moiré pattern. These are distinguished by the arrangement of the graphene lattice over the Rh(1 1 1) lattice. The symmetry sites of the Moiré unit cell are investigated by scanning tunneling microscopy and spectroscopy. The observed additional corrugation of the graphene sheet within a Moiré cell is the consequence of strain and electronic interactions between graphene and the Rh(1 1 1) substrate. The lattice period of the Moiré pattern depends on the in-plane rotation angle of the graphene layer with respect to the Rh(1 1 1) substrate. Scanning tunneling spectroscopy reveals a dependency of the local density of states on the hybridization of the π orbitals of the graphene with the d band of Rh(1 1 1). This results in a characteristic spectroscopic fingerprints of the individual symmetry sites of the Moiré pattern. [Display omitted]