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First-principles theory of low-energy electron diffraction and quantum interference in few-layer graphene

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 نشر من قبل John McClain III
 تاريخ النشر 2013
  مجال البحث فيزياء
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We present a computationally efficient method to incorporate density-functional theory into the calculation of reflectivity in low-energy electron microscopy. The reflectivity is determined by matching plane waves representing the electron beams to the Kohn-Sham wave functions calculated for a finite slab in a supercell. We show that the observed quantum interference effects in the reflectivity spectra of a few layers of graphene on a substrate can be reproduced well by the calculations using a moderate slab thickness.



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