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arXiv · 1108.5265

Plasmon and coupled plasmon-phonon modes in graphene in the presence of inter-band excitation channels

H. M. Dong·S. H. Zhang·W. Xu
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Abstract

Plasmon and coupled plasmon-phonon modes in graphene are investigated the-oretically within the diagrammatic self-consistent field theory. It shows that two plasmon modes and four coupled plasmon-phonon modes can be excited via intra-and inter-band transition channels. It is found that with increasing q and carrier density, the plasmon modes couple strongly with the optic-phonon modes in graphene. The coupled plasmon-phonon modes exhibit some interesting features which can be utilized to realize the plasmonic devices. Our results suggest that the carrier-phonon interaction should be considered to understand and explain the properties of elementary electronic excitations in graphene.

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H. M. Dong, S. H. Zhang, W. Xu. 2011-08-26. Plasmon and coupled plasmon-phonon modes in graphene in the presence of inter-band excitation channels. https://arxiv.org/abs/1108.5265

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