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Removing all periodic boundary conditions: Efficient non-equilibrium Green function calculations

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 نشر من قبل Nick Ruebner Papior
 تاريخ النشر 2019
  مجال البحث فيزياء
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We describe a method and its implementation for calculating electronic structure and electron transport without approximating the structure using periodic super-cells. This effectively removes spurious periodic images and interference effects. Our method is based on already established methods readily available in the non-equilibrium Green function formalism and allows for non-equilibrium transport. We present examples of a N defect in graphene, finite voltage bias transport in a point-contact to graphene, and a graphene-nanoribbon junction. This method is less costly, in terms of CPU-hours, than the super-cell approximation.



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