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The Role of Electron-electron Interactions in Graphene ARPES Spectra

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 نشر من قبل Reza Asgari
 تاريخ النشر 2007
  مجال البحث فيزياء
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We report on a theoretical study of the influence of electron-electron interactions on ARPES spectra in graphene that is based on the random-phase-approximation and on graphenes massless Dirac equation continuum model. We find that level repulsion between quasiparticle and plasmaron resonances gives rise to a gap-like feature at small k. ARPES spectra are sensitive to the electron-electron interaction coupling strength $alpha_{rm gr}$ and might enable an experimental determination of this material parameter.



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