Direct observation of a dispersionless impurity band in hydrogenated graphene

Author(s): Danny Haberer, Luca Petaccia, Mani Farjam, Simone Taioli, S. A. Jafari, Alexei Nefedov, Wu Zhang, Lucia Calliari, G. Scarduelli, Balazs Dora, D.V. Vyalikh, Thomas Pichler, Christof Wöll, Dario Alfe, Stefano Simonucci, Mildred S. Dresselhaus, Martin Knupfer, Bernd Büchner, Alexander Grüneis
Abstract: We show with angle-resolved photoemission spectroscopy that a new energy band appears in the electronic structure of electron-doped hydrogenated monolayer graphene (H-graphene). Its occupation can be controlled with the hydrogen amount and allows for tuning of graphene's doping level. Our calculations of the electronic structure of H-graphene suggest that this state is largely composed of hydrogen 1s orbitals and remains extended for low H coverages despite the random chemisorption of H. Further evidence for the existence of a hydrogen state is provided by x-ray absorption studies of undoped H-graphene which are clearly showing the emergence of an additional state in the vicinity of the pi* resonance.
Organisation(s): Electronic Properties of Materials
External organisation(s): Leibniz-Institut für Festkörper- und Werkstoffforschung Dresden, Elettra─Sincrotrone Trieste, Institute for Research in Fundamental Sciences (IPM), Università degli Studi di Trento, Karlsruher Institut für Technologie, University of Science and Technology of China (USTC), Budapest University of Technology and Economics, Technische Universität Dresden, University College London, Università degli Studi di Camerino, Massachusetts Institute of Technology
Journal: Physical Review B
Volume: 83
No. of pages: 6
ISSN: 1098-0121
DOI: https://doi.org/10.1103/PhysRevB.83.165433
Publication date: 2011
Peer reviewed: Yes
Austrian Fields of Science 2012: 103018 Materials physics
Portal url: https://ucris.univie.ac.at/portal/en/publications/direct-observation-of-a-dispersionless-impurity-band-in-hydrogenated-graphene(226cf456-1132-41b4-a878-6a2567deebe5).html