Cyclotron Resonance at the Dirac Point

ORAL

Abstract

We present high field infrared spectroscopy data on the n = -1 $\rightarrow$ 0 and n = 0 $\rightarrow$ 1 Landau Level (LL) transitions in graphene. At high magnetic fields, up to 31 T, measurements of single layer graphene show large shifts in the transition energies, which are suggestive of a gap in the n = 0 LL. The magnitude of these shifts are strongly enhanced over the bare Zeeman splitting naively expected for a spin-split state. We compare the field dependence of the shifts with proposed degeneracy-breaking mechanisms at the Dirac point.

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Authors

  • Paul Cadden-Zimansky

    Columbia University/NHMFL

  • Erik Henriksen

    Columbia University

  • Zhigang Jiang

    Georgia Institute of Technology, Georgia Tech University, School of physics, Georgia Institute of Technology, Atlanta, Georgia 30332

  • L.C. Tung

    NHMFL

  • Mollie Schwartz

    Columbia University

  • Y.J. Wang

    NHMFL, Florida State University, NHMFL

  • Philip Kim

    Columbia University, Physics, Columbia University, Depts. of Physics and Applied Physics, Columbia University, Physics Department, Columbia University, Associate Professor, Physics Department, Columbia University

  • Horst Stormer

    Columbia University/Bell Labs