Practical free-space quantum key distribution over 10 km in daylight and at night

  title={Practical free-space quantum key distribution over 10 km in daylight and at night},
  author={Richard J. Hughes and Jane E. Nordholt and Derek Derkacs and Charles G. Peterson},
  journal={New Journal of Physics},
We have demonstrated quantum key distribution (QKD) (Bennett C H and Brassard G 1984 Proc. IEEE Int. Conf. on Computers, Systems, and Signal Processing (Bangalore, India) p 175) over a 10 km, 1-airmass atmospheric range during daylight and at night. Secret random bit sequences of the quality required for the cryptographic keys used to initialize secure communications devices were transferred at practical rates with realistic security. By identifying the physical parameters that determine the… Expand

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