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arXiv · 2002.03672

Efficient decoy-states for the reference-frame-independent measurement-device-independent quantum key distribution

Feng-Yu Lu·Zhen-Qiang Yin·Guan-Jie Fan-Yuan·Rong Wang·Hang Liu·Shuang Wang·Wei Chen·De-Yong He
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Abstract

Reference-frame-independent measurement-device-independent quantum key distribution (RFI-MDI-QKD) is a novel protocol which eliminates all possible attacks on detector side and necessity of reference-frame alignment in source sides. However, its performance may degrade notably due to statistical fluctuations, since more parameters, e.g. yields and error rates for mismatched-basis events, must be accumulated to monitor the security. In this work, we find that the original decoy-states method estimates these yields over pessimistically since it ignores the potential relations between different bases. Through processing parameters of different bases jointly, the performance of RFI-MDI-QKD is greatly improved in terms of secret key rate and achievable distance when statistical fluctuations are considered. Our results pave an avenue towards practical RFI-MDI-QKD.

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Feng-Yu Lu, Zhen-Qiang Yin, Guan-Jie Fan-Yuan, Rong Wang, Hang Liu, Shuang Wang, Wei Chen, De-Yong He. 2020-02-10. Efficient decoy-states for the reference-frame-independent measurement-device-independent quantum key distribution. https://doi.org/10.1103/physreva.101.052318

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