International Journal of Quantum Information

Performance of reference-frame-independent quantum key distribution in underwater channel

Zhongqi Sun, Jipeng Wang, Zhenhua Li, Wenxiu Qu, Tianqi Dou, Fen Zhou, Haiqiang Ma

Published Feb 1, 2021• 3 citations

Abstract

During free-space quantum key distribution, the rotation and fluctuation of reference frame degrades the performance of quantum key distribution (QKD). Reference-frame-independent QKD (RFI-QKD) overcomes this issue effectively. To date, much theoretical and experimental research has been conducted on the performance of free-space RFI-QKD. However, these studies are all based on free-space air and satellite ground, and none have investigated the performance of RFI-QKD in an underwater channel. Therefore, this paper constructed a channel model that considered both scattering and optical attenuation to obtain an RFI-QKD secret key rate in an underwater channel. The simulation results confirm that even in a relatively harsh underwater scenario, RFI-QKD maintains good performance.

DOI: 10.1142/s0219749921500118

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