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arXiv · 0806.2684

Unconditional Security of Single-Photon Differential Phase Shift Quantum Key Distribution

Kai Wen·Kiyoshi Tamaki·Yoshihisa Yamamoto
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Abstract

In this Letter, we prove the unconditional security of single-photon differential phase shift quantum key distribution (DPS-QKD) protocol, based on the conversion to an equivalent entanglement-based protocol. We estimate the upper bound of the phase error rate from the bit error rate, and show that DPS-QKD can generate unconditionally secure key when the bit error rate is not greater than 4.12%. This proof is the first step to the unconditional security proof of coherent state DPS-QKD.

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Kai Wen, Kiyoshi Tamaki, Yoshihisa Yamamoto. 2009-10-04. Unconditional Security of Single-Photon Differential Phase Shift Quantum Key Distribution. https://doi.org/10.1103/physrevlett.103.170503

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