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Origin of the energy bandgap in epitaxial graphene

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 نشر من قبل Shuyun Zhou
 تاريخ النشر 2008
  مجال البحث فيزياء
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We studied the effect of quantum confinement on the size of the band gap in single layer epitaxial graphene. Samples with different graphene terrace sizes are studied by using low energy electron microscopy (LEEM) and angle-resolved photoemission spectroscopy (ARPES). The direct correlation between the terrace size extracted from LEEM and the gap size extracted from ARPES shows that quantum confinement alone cannot account for the large gap observed in epitaxial graphene samples.



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