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Localization and Kosterlitz-Thouless Transition in Disordered Graphene

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 نشر من قبل Yanyang Zhang
 تاريخ النشر 2008
  مجال البحث فيزياء
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We investigate disordered graphene with strong long-range impurities. Contrary to the common belief that delocalization should persist in such a system against any disorder, as the system is ex-pected to be equivalent to a disordered two-dimensional Dirac Fermionic system, we find that states near the Dirac points are localized for sufficiently strong disorder and the transition between the localized and delocalized states is of Kosterlitz-Thouless type. Our results show that the transition originates from bounding and unbounding of local current vortices.



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