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arXiv · 1701.06284

Ab initio calculation of the $G$ peak intensity of graphene: Combined study of the laser and Fermi energy dependence and importance of quantum interference effects

Sven Reichardt·Ludger Wirtz
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Abstract

We present the results of a diagrammatic, fully ab initio calculation of the $G$ peak intensity of graphene. The flexibility and generality of our approach enables us to go beyond the previous analytical calculations in the low-energy regime. We study the laser and Fermi energy dependence of the $G$ peak intensity and analyze the contributions from resonant and non-resonant electronic transitions. In particular, we explicitly demonstrate the importance of quantum interference and non-resonant states for the $G$ peak process. Our method of analysis and computational concept is completely general and can easily be applied to study other materials as well.

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Sven Reichardt, Ludger Wirtz. 2017-01-23. Ab initio calculation of the $G$ peak intensity of graphene: Combined study of the laser and Fermi energy dependence and importance of quantum interference effects. https://doi.org/10.1103/physrevb.95.195422

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