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Geometric magnetoconductance dips by edge roughness in graphene nanoribbons

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 نشر من قبل Hengyi Xu
 تاريخ النشر 2011
  مجال البحث فيزياء
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The magnetoconductance of graphene nanoribbons with rough zigzag and armchair edges is studied by numerical simulations. nanoribbons with sufficiently small bulk disorder show a pronounced magnetoconductance minimum at cyclotron radii close to the ribbon width, in close analogy to the wire peak observed in conventional semiconductor quantum wires. In zigzag nanoribbons, this feature becomes visible only above a threshold amplitude of the edge roughness, as a consequence of the reduced current density close to the edges.



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