Quantum key distribution over 122 km of standard telecom fiber

  title={Quantum key distribution over 122 km of standard telecom fiber},
  author={C. Gobby and Z. L. Yuan and Andrew J. Shields},
  journal={Applied Physics Letters},
We report a demonstration of quantum key distribution over a standard telecom fiber exceeding 100 km in length. Through careful optimization of the interferometer and single photon detector, we achieve a quantum bit error ratio of 8.9% for a 122 km link, allowing a secure shared key to be formed after error correction and privacy amplification. Key formation rates of up to 1.9 kbit/s are achieved depending upon fiber length. We discuss the factors limiting the maximum fiber length in quantum… 
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  • 2006
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