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arXiv · 1204.4177

Transconductance fluctuations as a probe for interaction induced quantum Hall states in graphene

Dong Su Lee·Viera Skakalova·R. Thomas Weitz·Klaus von Klitzing·Jurgen H. Smet
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Abstract

Transport measurements normally provide a macroscopic, averaged view of the sample, so that disorder prevents the observation of fragile interaction induced states. Here, we demonstrate that transconductance fluctuations in a graphene field effect transistor reflect charge localization phenomena on the nanometer scale due to the formation of a dot network which forms near incompressible quantum states. These fluctuations give access to fragile broken-symmetry and fractional quantum Hall states even though these states remain hidden in conventional magnetotransport quantities.

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Dong Su Lee, Viera Skakalova, R. Thomas Weitz, Klaus von Klitzing, Jurgen H. Smet. 2012-04-18. Transconductance fluctuations as a probe for interaction induced quantum Hall states in graphene. https://doi.org/10.1103/physrevlett.109.056602

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