2012/06/25 by V. N. Popov, Valentin N. Popov, Philippe Lambin +1 · 1 citation
Materials Science · Physics and Astronomy · #2D Materials and Applications #Boron and Carbon Nanomaterials Research #G band #Graphene #Graphene research and applications #Intensity (physics) #Materials science #Nanotechnology #Optics #Physics #Raman spectroscopy #cond-mat.mes-hall
paper · pdf · doi:10.1016/j.carbon.2012.11.006
published as Eur. Phys. J. B 85 (2012) 418/1-8
arxiv created 2012/06/25 · openalex publication_date 2012/11/23 · arxiv updated 2014/12/17 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The experimental Raman spectra of graphene exhibit a few intense two-phonon bands, which are enhanced through double-resonant scattering processes. Though there are many theoretical papers on this topic, none of them predicts the spectra within a single model. Here, we present results for the two-phonon Raman spectra of graphene calculated by means of the quantum perturbation theory. The electron and phonon dispersions, electronic lifetime, electron-photon and electron-phonon matrix elements, are all obtained within a density-functional-theory-based non-orthogonal tight-binding model. We study systematically the overtone and combination two-phonon Raman bands, and, in particular, the energy and polarization dependence of their Raman shift and intensity. We find that the ratio of the integrated intensities for parallel and cross polarized light for all two-phonon bands is between 0.33 and 0.42. Our results are in good agreement with the available experimental data.