Quantum Hall effect in dual-gated graphene bilayers with tunable layer density imbalance

Seyoung Kim; E. Tutuc

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arXiv · 0909.2288

Quantum Hall effect in dual-gated graphene bilayers with tunable layer density imbalance

Seyoung Kim·E. Tutuc

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Abstract

We study the magnetotransport properties of dual-gated graphene bilayers, in which the total density and layer density imbalance are independently controlled. As the bilayer is imbalanced we observe the emergence of a quantum Hall state (QHS) at filling factor $ν=0$ evinced by a plateau in the Hall conductivity, consistent with the opening of a gap between the electron and hole bands. By varying the layer density imbalance at fixed total density, we observe a suppression of the QHS at filling factors $ν=8$ and $ν=12$ when the layer densities are balanced, an observation at variance with theoretical expectations in the absence of electron-electron interaction and disorder.

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Seyoung Kim, E. Tutuc. 2009-09-12. Quantum Hall effect in dual-gated graphene bilayers with tunable layer density imbalance. https://arxiv.org/abs/0909.2288

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