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arXiv · 2405.16558

Refrence-Frame-Independent Quantum Key Distribution over 250 km of Optical Fiber

Xin Liu·Di Luo·Zhicheng Luo·Shizhuo Li·Zhenrong Zhang·Kejin Wei
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Abstract

The reference-frame-independent quantum key distribution (RFI QKD) protocol enables QKD systems to function effectively despite slowly varying reference frames, offering a distinct advantage in practical scenarios, particularly in mobile platforms. In this study, we successfully distribute secure key bits over a 250-km optical fiber distance by developing an RFI QKD system with a repetition rate of 150 MHz. Benefiting from high repetition rate, we achieve a finite-key secret key rate of 49.65 bit/s at a distance of 200 km, which is more than three times higher than state-of-the-art systems. Our work dramatically extends the transmission distance and enhances the secret key rate of RFI QKD, significantly promoting its practical application.

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Xin Liu, Di Luo, Zhicheng Luo, Shizhuo Li, Zhenrong Zhang, Kejin Wei. 2024-05-26. Refrence-Frame-Independent Quantum Key Distribution over 250 km of Optical Fiber. https://arxiv.org/abs/2405.16558

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