Electron-Lattice Coupling in Armchair Graphene Nanoribbons

J Phys Chem Lett. 2012 Oct 18;3(20):3039-42. doi: 10.1021/jz301247u. Epub 2012 Oct 5.

Abstract

We report the effects of electron-lattice coupling on the charge density distribution study of armchair graphene nanoribbons (GNRs). Here, we perform a theoretical investigation explaining the unexpected electronic density states observed experimentally. By means of a tight-binding approach with electron-lattice coupling, we obtained the same characteristic pattern of charge density along the C-C bonds suggested by both scanning tunneling and transmission electron microscopic measurements. Our results suggest electronic localized states whose sizes are dependent on the GNR width. We also show that our model rescues the quasi-particle charge-transport mechanism in GNRs. The remarkable agreement with experimental evidence allows us to conclude that our model could be, in many aspects, a fundamental tool when it comes to the phenomenological understanding of the charge behavior in this kind of system.

Keywords: charge-transport mechanism; electron−lattice coupling; graphene nanoribbons; quasi-particle; tight-binding approach.