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arXiv · 0707.1666

Velocity Renormalization and Carrier Lifetime in Graphene from Electron-Phonon Interaction

Cheol-Hwan Park·Feliciano Giustino·Marvin L. Cohen·Steven G. Louie
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Abstract

We present a first-principles investigation of the phonon-induced electron self-energy in graphene. The energy dependence of the self-energy reflects the peculiar linear bandstructure of graphene and deviates substantially from the usual metallic behavior. The effective band velocity of the Dirac fermions is found to be reduced by 4-8%, depending on doping, by the interaction with lattice vibrations. Our results are consistent with the observed linear dependence of the electronic linewidth on the binding energy in photoemission spectra.

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Cheol-Hwan Park, Feliciano Giustino, Marvin L. Cohen, Steven G. Louie. 2007-07-13. Velocity Renormalization and Carrier Lifetime in Graphene from Electron-Phonon Interaction. https://doi.org/10.1103/physrevlett.99.086804

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