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Practical Scheme To Share A Secret Key Through An Up To 27.6% Bit Error Rate Quantum Channel

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 نشر من قبل Chau Hoi Fung
 تاريخ النشر 2002
  مجال البحث فيزياء
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 تأليف H. F. Chau




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A secret key shared through quantum key distribution between two cooperative players is secure against any eavesdropping attack allowed by the laws of physics. Yet, such a key can be established only when the quantum channel error rate due to eavesdropping or imperfect apparatus is low. Here, I report a practical quantum key distribution scheme making use of an adaptive privacy amplification procedure with two-way classical communication. Then, I prove that the scheme generates a secret key whenever the bit error rate of the quantum channel is less than $0.5-0.1sqrt{5} approx 27.6%$, thereby making it the most error resistant scheme known to date.



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