Anisotropic Eliashberg function and electron-phonon coupling in doped graphene
- Author(s)
- D. Haberer, L. Petaccia, A. V. Fedorov, C. S. Praveen, S. Fabris, S. Piccinin, O. Vilkov, D. V. Vyalikh, A. Preobrajenski, N. I. Verbitskiy, H. Shiozawa, J. Fink, M. Knupfer, B. Buechner, Alexander Grüneis
- Abstract
We investigate, with high-resolution angle-resolved photoemission
spectroscopy, the spectral function of potassium-doped
quasi-free-standing graphene on Au. Angle-dependent x-ray photoemission
and density functional theory calculations demonstrate that potassium
intercalates into the graphene/Au interface, leading to an upshift of
the K-derived electronic band above the Fermi level. This empty band is
what makes this system perfectly suited to disentangle the contributions
to electron-phonon coupling coming from the π band and K-derived bands. From a self-energy analysis we find an anisotropic electron-phonon coupling strength λ of 0.1 (0.2) for the KΓ (KM)
high-symmetry directions in momentum space, respectively.
Interestingly, the high-energy part of the Eliashberg function which
relates to graphene's optical phonons is equal in both directions but
only in KM does an additional low-energy part appear.
- Organisation(s)
- Electronic Properties of Materials
- External organisation(s)
- Leibniz-Institut für Festkörper- und Werkstoffforschung Dresden, University of California, Berkeley, Elettra-Sincrotrone Trieste S.C.p.A., Saint Petersburg State University, Theory@Elettra, Scuola Internazionale Superiore di Studi Avanzati, Technische Universität Dresden, Lund University
- Journal
- Physical Review B
- Volume
- 88
- No. of pages
- 5
- ISSN
- 1098-0121
- DOI
- https://doi.org/10.1103/PhysRevB.88.081401
- Publication date
- 08-2013
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103020 Surface physics, 103009 Solid state physics, 103018 Materials physics
- Keywords
- Portal url
- https://ucris.univie.ac.at/portal/en/publications/anisotropic-eliashberg-function-and-electronphonon-coupling-in-doped-graphene(d974a19f-c088-445a-b474-24e02cab88db).html