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Decoherence and disorder in quantum walks: From ballistic spread to localization

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 نشر من قبل Andreas Schreiber
 تاريخ النشر 2011
  مجال البحث فيزياء
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We investigate the impact of decoherence and static disorder on the dynamics of quantum particles moving in a periodic lattice. Our experiment relies on the photonic implementation of a one-dimensional quantum walk. The pure quantum evolution is characterized by a ballistic spread of a photons wave packet along 28 steps. By applying controlled time-dependent operations we simulate three different environmental influences on the system, resulting in a fast ballistic spread, a diffusive classical walk and the first Anderson localization in a discrete quantum walk architecture.



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