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High transmission in twisted bilayer graphene with angle disorder

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 نشر من قبل H\\'ector Sainz-Cruz
 تاريخ النشر 2021
  مجال البحث فيزياء
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Angle disorder is an intrinsic feature of twisted bilayer graphene and other moire materials. Here, we discuss electron transport in twisted bilayer graphene in the presence of angle disorder. We compute the local density of states and the Landauer-Buttiker transmission through an angle disorder barrier of width comparable to the moire period, using a decimation technique based on a real space description. We find that barriers which separate regions where the width of the bands differ by 50% or more lead to a minor suppression of the transmission, and that the transmission is close to one for normal incidence, which is reminiscent of Klein tunneling. These results suggest that transport in twisted bilayer graphene is weakly affected by twist angle disorder.



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