Raman intensity of graphene

Abstract

The Raman scattering process in graphene is always resonant, i.e. involves real electronic states, and this affects the Raman intensity. Thus, a detailed analysis of the Raman intensity of graphene can provide useful information on the Raman scattering process itself, in particular on the interaction between the fundamental excitations in graphene, such as electron–phonon and electron-defect interactions, which can be studied only by transport or complex techniques. Here a detailed analysis of the dependence of the Raman intensity of graphene on doping and disorder is presented. While the intensity of the G peak, I(G), is not strongly affected by small amount of doping or disorder, the intensity of the 2D peak strongly decreases with increasing doping or disorder. By analyzing the dependence of I(2D) with doping in the framework of a fully resonant process, we measured the total electron–phonon scattering rate.