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arXiv · 0711.3526

Unconditionally secure quantum key-distribution with relatively strong signal pulse

Kiyoshi Tamaki
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Abstract

We propose an unconditionally secure quantum key distribution (QKD) protocol, which uses a relatively strong signal pulse. While our protocol shares similar security bases as the Bennett 1992 protocol with a strong reference pulse (B92), our scheme uses a smaller number of detectors and it is robust against Rayleigh scattering in an optical fibre. We derive a lower bound of secret key generation rate of our protocol and show that our protocol can cover relatively long distances, assuming precise phase modulations and stable interferometers.

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Kiyoshi Tamaki. 2007-11-22. Unconditionally secure quantum key-distribution with relatively strong signal pulse. https://doi.org/10.1103/physreva.77.032341

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