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arXiv · 1207.5544

Security of distributed-phase-reference quantum key distribution

Tobias Moroder·Marcos Curty·Charles Ci Wen Lim·Le Phuc Thinh·Hugo Zbinden·Nicolas Gisin
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Abstract

Distributed-phase-reference quantum key distribution stands out for its easy implementation with present day technology. Since many years, a full security proof of these schemes in a realistic setting has been elusive. For the first time, we solve this long standing problem and present a generic method to prove the security of such protocols against general attacks. To illustrate our result we provide lower bounds on the key generation rate of a variant of the coherent-one-way quantum key distribution protocol. In contrast to standard predictions, it appears to scale quadratically with the system transmittance.

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Tobias Moroder, Marcos Curty, Charles Ci Wen Lim, Le Phuc Thinh, Hugo Zbinden, Nicolas Gisin. 2012-07-23. Security of distributed-phase-reference quantum key distribution. https://doi.org/10.1103/physrevlett.109.260501

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