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Long-distance quantum key distribution in optical fibre



Philip A. Hiskett, Danna Rosenberg, Charles G. Peterson, Richard J. Hughes, Jane E. Nordholt, Sae Woo Nam, Adriana Lita, Aaron J. Miller


Use of low-noise detectors can both increase the secret bit rate of long-distance quantum key distribution (QKD) and dramatically extend the length of a fibre optic link over which secure keys can be distributed. Previous work has demonstrated the use of ultra-low-noise transition-edge sensors (TESs) in a QKD system with transmission over 50 km. In this study, we demonstrate the potential of the TESs by successfully generating an error-corrected, privacy-amplified key over 148.7 km of dark optical fibre at a mean photon number υ = 0.1, or 184.6 km of dark optical fiber at a mean photon number of 0.5. We have also exchanged secret keys over 67.5 km, that is secure against powerful photon-number-splitting (PNS) attacks.
New Journal of Physics


cryptography, quantum information, quantum key distribution, single photon detectors, superconductors, transition-edge sensor


Hiskett, P. , Rosenberg, D. , Peterson, C. , Hughes, R. , Nordholt, J. , Nam, S. , Lita, A. and Miller, A. (2006), Long-distance quantum key distribution in optical fibre, New Journal of Physics, [online], (Accessed April 21, 2024)
Created September 13, 2006, Updated October 12, 2021