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arXiv · 1908.02420

Disorder induced helical-edge transport near $\nu$=0 of monolayer graphene

Sung Ju Hong·Christopher Belke·Johannes C. Rode·Benedikt Brechtken·Rolf J. Haug
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Abstract

The complex nature of filling factor $\nu$=0 of monolayer graphene is studied in magnetotransport experiments. As function of perpendicular magnetic field a metal-insulator transition is observed, which is attributed to disorder-induced Landau level broadening in the canted antiferromagnetic phase. In the metallic regime a separation of the zeroth Landau level appears and signs of the quantum spin Hall effect are seen near $\nu$=0. In addition to local transport, nonlocal transport experiments show results being consistent with helical edge transport.

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Sung Ju Hong, Christopher Belke, Johannes C. Rode, Benedikt Brechtken, Rolf J. Haug. 2019-08-07. Disorder induced helical-edge transport near $\nu$=0 of monolayer graphene. https://arxiv.org/abs/1908.02420

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