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arXiv · 1511.01541

Unconventional Correlation between Quantum Hall Transport Quantization and Bulk State Filling in Gated Graphene Devices

Yong-Tao Cui·Bo Wen·Eric Y. Ma·Georgi Diankov·Zheng Han·Francois Amet·Takashi Taniguchi·Kenji Watanabe·David Goldhaber-Gordon·Cory R. Dean·Zhi-Xun Shen
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Abstract

We report simultaneous transport and scanning microwave impedance microscopy to examine the correlation between transport quantization and filling of the bulk Landau levels in the quantum Hall regime in gated graphene devices. Surprisingly, a comparison of these measurements reveals that quantized transport typically occurs below the complete filling of bulk Landau levels, when the bulk is still conductive. This result points to a revised understanding of transport quantization when carriers are accumulated by gating. We discuss the implications on transport study of the quantum Hall effect in graphene and related topological states in other two-dimensional electron systems.

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Yong-Tao Cui, Bo Wen, Eric Y. Ma, Georgi Diankov, Zheng Han, Francois Amet, Takashi Taniguchi, Kenji Watanabe, David Goldhaber-Gordon, Cory R. Dean, Zhi-Xun Shen. 2016-10-28. Unconventional Correlation between Quantum Hall Transport Quantization and Bulk State Filling in Gated Graphene Devices. https://doi.org/10.1103/physrevlett.117.186601

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