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Effects of Screening on Propagation of Graphene Surface Plasmons

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 نشر من قبل Kenichi Sasaki
 تاريخ النشر 2014
  مجال البحث فيزياء
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Electromagnetic fields bound tightly to charge carriers in a two-dimensional sheet, namely surface plasmons, are shielded by metallic plates that are a part of a device. It is shown that for epitaxial graphenes, the propagation velocity of surface plasmons is suppressed significantly through a partial screening of the electron charge by the interface states. On the basis of analytical calculations of the electron lifetime determined by the screened Coulomb interaction, we show that the screening effect gives results in agreement with those of a recent experiment.



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