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arXiv · 1505.08076

Experimental Passive Round-Robin Differential Phase-Shift Quantum Key Distribution

Jian-Yu Guan·Zhu Cao·Yang Liu·Guo-Liang Shen-Tu·Jason S. Pelc·M. M. Fejer·Cheng-Zhi Peng·Xiongfeng Ma·Qiang Zhang·Jian-Wei Pan
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Abstract

In quantum key distribution (QKD), the bit error rate is used to estimate the information leakage and hence determines the amount of privacy amplification --- making the final key private by shortening the key. In general, there exists a threshold of the error rate for each scheme, above which no secure key can be generated. This threshold puts a restriction on the environment noises. For example, a widely used QKD protocol --- BB84 --- cannot tolerate error rates beyond 25%. A new protocol, round-robin differential phase shifted (RRDPS) QKD, essentially removes this restriction and can in principle tolerate more environment disturbance. Here, we propose and experimentally demonstrate a passive RRDPS QKD scheme. In particular, our 500 MHz passive RRDPS QKD system is able to generate a secure key over 50 km with a bit error rate as high as 29%. This scheme should find its applications in noisy environment conditions.

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Jian-Yu Guan, Zhu Cao, Yang Liu, Guo-Liang Shen-Tu, Jason S. Pelc, M. M. Fejer, Cheng-Zhi Peng, Xiongfeng Ma, Qiang Zhang, Jian-Wei Pan. 2015-05-29. Experimental Passive Round-Robin Differential Phase-Shift Quantum Key Distribution. https://doi.org/10.1103/physrevlett.114.180502

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