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arXiv · 1107.3929

Coexistence of electron and hole transport in graphene

S. Wiedmann·H. J. van Elferen·E. V. Kurganova·M. I. Katsnelson·A. J . M. Giesbers·A. Veligura·B. J. van Wees·R. V. Gorbachev·K. S. Novoselov·J. C. Maan·U. Zeitler
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Abstract

When sweeping the carrier concentration in monolayer graphene through the charge neutrality point, the experimentally measured Hall resistivity shows a smooth zero crossing. Using a two- component model of coexisting electrons and holes around the charge neutrality point, we unambiguously show that both types of carriers are simultaneously present. For high magnetic fields up to 30 T the electron and hole concentrations at the charge neutrality point increase with the degeneracy of the zero-energy Landau level which implies a quantum Hall metal state at \nu=0 made up by both electrons and holes.

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S. Wiedmann, H. J. van Elferen, E. V. Kurganova, M. I. Katsnelson, A. J . M. Giesbers, A. Veligura, B. J. van Wees, R. V. Gorbachev, K. S. Novoselov, J. C. Maan, U. Zeitler. 2011-07-20. Coexistence of electron and hole transport in graphene. https://doi.org/10.1103/physrevb.84.115314

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