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arXiv · 1310.2824

Coupled plasmon - phonon excitations in extrinsic monolayer graphene

V. U. Nazarov·F. Alharbi·T. S. Fisher·S. Kais
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Abstract

The existence of an acoustic plasmon in extrinsic (doped or gated) monolayer graphene was found recently in an {\it ab initio} calculation with the frozen lattice [M. Pisarra {\it et al.}, arXiv:1306.6273, 2013]. By the {\em fully dynamic} density-functional perturbation theory approach, we demonstrate a strong coupling of the acoustic plasmonic mode to lattice vibrations. Thereby, the acoustic plasmon in graphene does not exist as an isolated excitation, but it is rather bound into a combined plasmon-phonon mode. We show that the coupling provides a mechanism for the {\em bidirectional} energy exchange between the electronic and the ionic subsystems with fundamentally, as well as practically, important implications for the lattice cooling and heating by electrons in graphene.

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V. U. Nazarov, F. Alharbi, T. S. Fisher, S. Kais. 2013-10-10. Coupled plasmon - phonon excitations in extrinsic monolayer graphene. https://doi.org/10.1103/physrevb.89.195423

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