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arXiv · 0912.3179

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

Jairo Velasco Jr.·Gang Liu·Lei Jing·Philip Kratz·Wenzhong Bao·Marc Bockrath·Chun Ning Lau
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Abstract

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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Jairo Velasco Jr., Gang Liu, Lei Jing, Philip Kratz, Wenzhong Bao, Marc Bockrath, Chun Ning Lau. 2009-12-16. Probing Charging and Localization in the Quantum Hall Regime by Graphene pnp Junctions. https://doi.org/10.1103/physrevb.81.121407

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