Kinks in the σ Band of Graphene Induced by Electron-Phonon Coupling
2013 (English)In: Physical Review Letters, ISSN 0031-9007, Vol. 111, no 21, 216806- p.Article in journal (Refereed) Published
Angle-resolved photoemission spectroscopy reveals pronounced kinks in the dispersion of the σ band of graphene. Such kinks are usually caused by the combination of a strong electron-boson interaction and the cutoff in the Fermi-Dirac distribution. They are therefore not expected for the σ band of graphene that has a binding energy of more than ≈3.5 eV. We argue that the observed kinks are indeed caused by the electron-phonon interaction, but the role of the Fermi-Dirac distribution cutoff is assumed by a cutoff in the density of σ states. The existence of the effect suggests a very weak coupling of holes in the σ band not only to the π electrons of graphene but also to the substrate electronic states. This is confirmed by the presence of such kinks for graphene on several different substrates that all show a strong coupling constant of λ≈1.
Place, publisher, year, edition, pages
American Physical Society , 2013. Vol. 111, no 21, 216806- p.
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-102495DOI: 10.1103/PhysRevLett.111.216806ISI: 000327246200003OAI: oai:DiVA.org:liu-102495DiVA: diva2:679188
Funding Agencies|Lundbeck Foundation||VILLUM Foundation||Danish Council for Independent Research/Technology and Production Sciences||Swedish Research Council||Knut and Alice Wallenberg Foundations||2013-12-132013-12-122013-12-28