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Daylight operation of a free space, entanglement-based quantum key distribution system

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 نشر من قبل Christian Kurtsiefer
 تاريخ النشر 2008
  مجال البحث فيزياء
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Many quantum key distribution (QKD) implementations using a free space transmission path are restricted to operation at night time in order to distinguish the signal photons used for a secure key establishment from background light. Here, we present a lean entanglement-based QKD system overcoming that imitation. By implementing spectral, spatial and temporal filtering techniques, we were able to establish a secure key continuously over several days under varying light and weather conditions.



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