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Spectro-microscopy of single and multi-layer graphene supported by a weakly interacting substrate

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 نشر من قبل Kevin Knox
 تاريخ النشر 2008
  مجال البحث فيزياء
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We report measurements of the electronic structure and surface morphology of exfoliated graphene on an insulating substrate using angle-resolved photoemission and low energy electron diffraction. Our results show that although exfoliated graphene is microscopically corrugated, the valence band retains a massless fermionic dispersion, with a Fermi velocity of ~10^6 m/s. We observe a close relationship between the morphology and electronic structure, which suggests that controlling the interaction between graphene and the supporting substrate is essential for graphene device applications.



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