Fano-Profiles in HOPG and graphene flakes
- We investigated the electronic structure of the valence and conduction band of HOPG by 2D resonant photoemission spectroscopy. Our aim is to understand the electronic structure of defects and inhomogeneities in graphene and related materials in more detail. From our measurements we find that the transition from the sigma-band to the pi*-band at the M-point shows a characteristic Fano-Profile. A Fano-Profile occurs as the result of the interference of the band to band transition and a parallel transition to a discrete energy level within the band gap. The theory of Fano enables us to determine the energetic location of these discrete level. It is found to be several meV above the Fermi-Energy. Additional measurements on graphene flakes lead to similar results for the sigma- to pi*-band transition and the location of the discrete energy state. With this we not only can determine the energetic states of defects but also get a better understanding of the origin of the Fano profile which is a particular detail of the resonant absorptionWe investigated the electronic structure of the valence and conduction band of HOPG by 2D resonant photoemission spectroscopy. Our aim is to understand the electronic structure of defects and inhomogeneities in graphene and related materials in more detail. From our measurements we find that the transition from the sigma-band to the pi*-band at the M-point shows a characteristic Fano-Profile. A Fano-Profile occurs as the result of the interference of the band to band transition and a parallel transition to a discrete energy level within the band gap. The theory of Fano enables us to determine the energetic location of these discrete level. It is found to be several meV above the Fermi-Energy. Additional measurements on graphene flakes lead to similar results for the sigma- to pi*-band transition and the location of the discrete energy state. With this we not only can determine the energetic states of defects but also get a better understanding of the origin of the Fano profile which is a particular detail of the resonant absorption process.…
Author: | Matthias Städter, Matthias RichterGND, Dieter SchmeißerORCiD |
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URL: | http://www.dpg-verhandlungen.de/year/2013/conference/regensburg/part/hl/session/52/contribution/5?lang=de |
Title of the source (German): | Verhandlungen der Deutschen Physikalischen Gesellschaft |
Publisher: | Deutsche Physikalische Gesellschaft |
Place of publication: | Bad Honnef |
Document Type: | Conference Proceeding |
Language: | English |
Year of publication: | 2013 |
Tag: | Fano profiles; Graphene; HOPG; resonant photoelectron spectroscopy |
Series ; volume number: | Verhandlungen der Deutschen Physikalischen Gesellschaft ; Reihe 6, Band 48 |
Faculty/Chair: | Fakultät 1 MINT - Mathematik, Informatik, Physik, Elektro- und Informationstechnik / FG Angewandte Physik und Halbleiterspektroskopie |