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arXiv · 1010.1919

Gate-Defined Graphene Quantum Point Contact in the Quantum Hall Regime

S. Nakaharai·J. R. Williams·C. M. Marcus
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Abstract

We investigate transport in a gate-defined graphene quantum point contact in the quantum Hall regime. Edge states confined to the interface of p and n regions in the graphene sheet are controllably brought together from opposite sides of the sample and allowed to mix in this split-gate geometry. Among the expected quantum Hall features, an unexpected additional plateau at 0.5 h/e^2 is observed. We propose that chaotic mixing of edge channels gives rise to the extra plateau.

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S. Nakaharai, J. R. Williams, C. M. Marcus. 2010-10-10. Gate-Defined Graphene Quantum Point Contact in the Quantum Hall Regime. https://doi.org/10.1103/physrevlett.107.036602

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