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Tilted potential induced coupling of localized states in a graphene nanoconstriction

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 نشر من قبل Malcolm Connolly
 تاريخ النشر 2010
  مجال البحث فيزياء
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We use the charged tip of a low temperature scanning probe microscope to perturb the transport through a graphene nanoconstriction. Maps of the conductance as a function of tip position display concentric halos, and by following the expansion of the halos with back-gate voltage we are able to identify an elongated domain over the nanoconstriction where they originate. Amplitude modulations of the transmission resonances are correlated with the gradient of the tip-induced potential and we analyze this in terms of modified coupling between localized states.

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