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arXiv · 1506.06680

SU(4) symmetry breaking revealed by magneto-optical spectroscopy in epitaxial graphene

Liang Z. Tan·Milan Orlita·Marek Potemski·James Palmer·Claire Berger·Walter A. de Heer·Steven G. Louie·Gérard Martinez
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Abstract

Refined infrared magnetotransmission experiments have been performed in magnetic fields B up to 35 T on a series of multilayer epitaxial graphene samples. Following the main optical transition involving the n=0 Landau level (LL), we observe a new absorption transition increasing in intensity with magnetic fields B>26 T. Our analysis shows that this is a signature of the breaking of the SU(4) symmetry of the n=0 LL. Using a quantitative model, we show that the only symmetry-breaking scheme consistent with our experiments is a charge density wave (CDW).

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Liang Z. Tan, Milan Orlita, Marek Potemski, James Palmer, Claire Berger, Walter A. de Heer, Steven G. Louie, Gérard Martinez. 2015-06-22. SU(4) symmetry breaking revealed by magneto-optical spectroscopy in epitaxial graphene. https://doi.org/10.1103/physrevb.91.235122

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