1. Screening of electron-phonon coupling in graphene on Ir(111)
- Author
-
Jörg Kröger, Alejandro Molina-Sanchez, Ludger Wirtz, M. Endlich, Technische Universität Ilmenau (TU ), Physics and Materials Science Research Unit, University of Luxembourg, University of Luxembourg [Luxembourg], Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF), M.E. and J.K. acknowledge funding by the Carl-Zeiss foundation. A.M. and L.W. acknowledge funding by the French National Research Agency through ANR-09-BLAN-0421-01. Calculations were performed at the IDRIS supercomputing center, Orsay (Project No. 091827), and at the Tirant Supercomputer of the University of Valencia (group vlc44)., and ANR-09-BLAN-0421,ETSFG(2009)
- Subjects
Materials science ,Phonon ,Physics [G04] [Physical, chemical, mathematical & earth Sciences] ,FOS: Physical sciences ,Physics::Optics ,02 engineering and technology ,Electron ,01 natural sciences ,law.invention ,Condensed Matter::Materials Science ,[SPI]Engineering Sciences [physics] ,law ,0103 physical sciences ,Physics::Atomic and Molecular Clusters ,Graphite ,Physics::Chemical Physics ,010306 general physics ,Kohn anomaly ,Condensed Matter - Materials Science ,Condensed matter physics ,Graphene ,Materials Science (cond-mat.mtrl-sci) ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Coupling (probability) ,Electronic, Optical and Magnetic Materials ,Brillouin zone ,Physique [G04] [Physique, chimie, mathématiques & sciences de la terre] ,Condensed Matter::Strongly Correlated Electrons ,0210 nano-technology ,Dispersion (chemistry) - Abstract
The phonon dispersion of graphene on Ir(111) has been determined by means of angle-resolved inelastic electron scattering and density functional calculations. Kohn anomalies of the highest optical-phonon branches are observed at the $\overline{\ensuremath{\Gamma}}$ and $\overline{\text{K}}$ point of the surface Brillouin zone. At $\overline{\text{K}}$ the Kohn anomaly is weaker than observed for pristine graphene and graphite. This observation is rationalized in terms of a decrease of the electron-phonon coupling due to screening of graphene electron correlations by the metal substrate.
- Published
- 2013