Berlin 2012 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 27: Graphene II
O 27.5: Vortrag
Dienstag, 27. März 2012, 11:30–11:45, MA 041
Electronic properties of Ni adatoms on graphene — •Mike Gyamfi1, Thomas Eelbo1, Marta Waśniowska1, Tim O. Wehling2, Stiven Forti3, Ulrich Starke3, Alexander I. Lichtenstein2, Mikhail I. Katsnelson4, and Roland Wiesendanger1 — 1Institute of Applied Physics, University of Hamburg, Hamburg, Germany — 21st Institute of Theoretical Physics, University of Hamburg, Hamburg, Germany — 3Max Planck Institute for Solid State Research, Stuttgart, Germany — 4Institute for Molecules and Materials, Radboud University of Nijmegen, Nijmegen,The Netherlands
We investigated Ni adatoms adsorbed on epitaxial monolayer graphene grown on the silicon terminated SiC(0001) surface by means of scanning tunneling microscopy (STM) and spectroscopy (STS).
The experiments were performed at 5 K and Ni was evaporated on the sample at 12 K which results in the adsorption of well isolated monomers. STM images with atomic resolution of the graphene lattice reveal all Ni atoms being located on the same adsorption site, i.e. on the center of a carbon hexagon. The electronic structure of the monomers is characterized by pronounced peaks below the Fermi energy which are related to Ni d-states. Due to the interaction with the substrate the electronic configuration of the Ni atoms is predominantly d10 and consequently the monomers are nonmagnetic. Furthermore, we observed an orbital selective coupling between the Ni adatoms and the Dirac electrons of graphene. The experimental results are compared to theoretical calculations.