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arXiv · 1104.0438

Quantum Hall effect and Landau level crossing of Dirac fermions in trilayer graphene

Thiti Taychatanapat·Kenji Watanabe·Takashi Taniguchi·Pablo Jarillo-Herrero
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Abstract

We investigate electronic transport in high mobility (\textgreater 100,000 cm$^2$/V$\cdot$s) trilayer graphene devices on hexagonal boron nitride, which enables the observation of Shubnikov-de Haas oscillations and an unconventional quantum Hall effect. The massless and massive characters of the TLG subbands lead to a set of Landau level crossings, whose magnetic field and filling factor coordinates enable the direct determination of the Slonczewski-Weiss-McClure (SWMcC) parameters used to describe the peculiar electronic structure of trilayer graphene. Moreover, at high magnetic fields, the degenerate crossing points split into manifolds indicating the existence of broken-symmetry quantum Hall states.

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Thiti Taychatanapat, Kenji Watanabe, Takashi Taniguchi, Pablo Jarillo-Herrero. 2011-04-03. Quantum Hall effect and Landau level crossing of Dirac fermions in trilayer graphene. https://doi.org/10.1038/nphys2008

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