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

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 نشر من قبل Cheol-Hwan Park
 تاريخ النشر 2007
  مجال البحث فيزياء
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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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