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arXiv · 1112.5368

Field induced quantum-Hall ferromagnetism in suspended bilayer graphene

H. J. van Elferen·A. Veligura·E. V. Kurganova·U. Zeitler·J. C. Maan·N. Tombros·I. J. Vera-Marun·B. J. van Wees
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Abstract

We have measured the magneto-resistance of freely suspended high-mobility bilayer graphene. For magnetic fields $B>1$ T we observe the opening of a field induced gap at the charge neutrality point characterized by a diverging resistance. For higher fields the eight-fold degenerated lowest Landau level lifts completely. Both the sequence of this symmetry breaking and the strong transition of the gap-size point to a ferromagnetic nature of the insulating phase developing at the charge neutrality point.

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H. J. van Elferen, A. Veligura, E. V. Kurganova, U. Zeitler, J. C. Maan, N. Tombros, I. J. Vera-Marun, B. J. van Wees. 2012-02-27. Field induced quantum-Hall ferromagnetism in suspended bilayer graphene. https://doi.org/10.1103/physrevb.85.115408

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