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Probing Charging and Localization in the Quantum Hall Regime by Graphene pnp Junctions

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 نشر من قبل Chun Ning (Jeanie) Lau
 تاريخ النشر 2009
  مجال البحث فيزياء
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Using high quality graphene pnp junctions, we observe prominent conductance fluctuations on transitions between quantum Hall (QH) plateaus as the top gate voltage Vtg is varied. In the Vtg-B plane, the fluctuations form crisscrossing lines that are parallel to those of the adjacent plateaus, with different temperature dependences for the conductance peaks and valleys. These fluctuations arise from Coulomb-induced charging of electron- or hole-doped localized states when the device bulk is delocalized, underscoring the importance of electronic interactions in graphene in the QH regime.



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