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

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 نشر من قبل Liang Zheng Tan
 تاريخ النشر 2015
  مجال البحث فيزياء
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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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