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arXiv · 0810.1069

Gigahertz decoy quantum key distribution with 1 Mbit/s secure key rate

A. R. Dixon·Z. L. Yuan·J. F. Dynes·A. W. Sharpe·A. J. Shields
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Abstract

We report the first gigahertz clocked decoy-protocol quantum key distribution (QKD). Record key rates have been achieved thanks to the use of self-differencing InGaAs avalanche photodiodes designed specifically for high speed single photon detection. The system is characterized with a secure key rate of 1.02 Mbit/s for a fiber distance of 20 km and 10.1 kbit/s for 100 km. As the present advance relies upon compact non-cryogenic detectors, it opens the door towards practical and low cost QKD systems to secure broadband communication in future.

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A. R. Dixon, Z. L. Yuan, J. F. Dynes, A. W. Sharpe, A. J. Shields. 2008-10-06. Gigahertz decoy quantum key distribution with 1 Mbit/s secure key rate. https://doi.org/10.1364/oe.16.018790

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