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arXiv · 1606.08375

Two-dimensional distributed-phase-reference protocol for quantum key distribution

Davide Bacco·Jesper Bjerge Christensen·Mario A. Usuga Castaneda·Yunhong Ding·Søren Forchhammer·Karsten Rottwitt·Leif Katsuo Oxenløwe
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Abstract

Quantum key distribution (QKD) and quantum communication enable the secure exchange of information between remote parties. Currently, the distributed-phase-reference (DPR) protocols, which are based on weak coherent pulses, are among the most practical solutions for long-range QKD. During the last 10 years, long-distance fiber-based DPR systems have been successfully demonstrated, although fundamental obstacles such as intrinsic channel losses limit their performance. Here, we introduce the first two-dimensional DPR-QKD protocol in which information is encoded in the time and phase of weak coherent pulses. The ability of extracting two bits of information per detection event, enables a higher secret key rate in specific realistic network scenarios. Moreover, despite the use of more dimensions, the proposed protocol remains simple, practical, and fully integrable.

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Davide Bacco, Jesper Bjerge Christensen, Mario A. Usuga Castaneda, Yunhong Ding, Søren Forchhammer, Karsten Rottwitt, Leif Katsuo Oxenløwe. 2016-06-27. Two-dimensional distributed-phase-reference protocol for quantum key distribution. https://arxiv.org/abs/1606.08375

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