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arXiv · 0901.4215

Graphite from the viewpoint of Landau level spectroscopy: An effective graphene bilayer and monolayer

M. Orlita·C. Faugeras·J. M. Schneider·G. Martinez·D. K. Maude·M. Potemski
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Abstract

We describe an infrared transmission study of a thin layer of bulk graphite in magnetic fields up to B = 34 T. Two series of absorption lines whose energy scales as sqrtB and B are present in the spectra and identified as contributions of massless holes at the H point and massive electrons in the vicinity of the K point, respectively. We find that the optical response of the K point electrons corresponds, over a wide range of energy and magnetic field, to a graphene bilayer with an effective inter-layer coupling 2γ_1, twice the value for a real graphene bilayer, which reflects the crystal ordering of bulk graphite along the c-axis. The K point electrons thus behave as massive Dirac fermions with a mass enhanced twice in comparison to a true graphene bilayer.

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M. Orlita, C. Faugeras, J. M. Schneider, G. Martinez, D. K. Maude, M. Potemski. 2009-01-27. Graphite from the viewpoint of Landau level spectroscopy: An effective graphene bilayer and monolayer. https://doi.org/10.1103/physrevlett.102.166401

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