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Attraction-repulsion transition in the interaction of adatoms and vacancies in graphene

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 نشر من قبل Stephan LeBohec
 تاريخ النشر 2013
  مجال البحث فيزياء
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The interaction of two resonant impurities in graphene has been predicted to have a long-range character with weaker repulsion when the two adatoms reside on the same sublattice and stronger attraction when they are on different sublattices. We reveal that this attraction results from a single energy level. This opens up a possibility of controlling the sign of the impurity interaction via the adjustment of the chemical potential. For many randomly distributed impurities (adatoms or vacancies) this may offer a way to achieve a controlled transition from aggregation to dispersion.

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