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arXiv · 2212.11534

Sub-Mbps key-rate continuous-variable quantum key distribution with local-local-oscillator over 100 km fiber

Yaodi Pi·Heng Wang·Yan Pan·Yun Shao·Yang Li·Jie Yang·Yichen Zhang·Wei Huang·Bingjie Xu
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Abstract

We experimentally demonstrated a sub-Mbps key rate Gaussian-modulated coherent-state continuous-variable quantum key distribution (CV-QKD) over 100 km transmission distance. To efficiently control the excess noise, the quantum signal and the pilot tone are co-transmitted in fiber channel based on wide-band frequency and polarization multiplexing methods. Furthermore, a high-accuracy data-assisted time domain equalization algorithm is carefully designed to compensate the phase noise and polarization variation in low signal-to-noise ratio. The asymptotic secure key rate (SKR) of the demonstrated CV-QKD is experimentally evaluated to be 10.36 Mbps, 2.59 Mbps, and 0.69 Mbps over transmission distance of 50 km, 75 km, and 100 km, respectively. The experimental demonstrated CV-QKD system significantly improves transmission distance and SKR compared to the state-of-art GMCS CV-QKD experimental results, and shows the potential for long-distance and high-speed secure quantum key distribution.

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Yaodi Pi, Heng Wang, Yan Pan, Yun Shao, Yang Li, Jie Yang, Yichen Zhang, Wei Huang, Bingjie Xu. 2022-12-22. Sub-Mbps key-rate continuous-variable quantum key distribution with local-local-oscillator over 100 km fiber. https://doi.org/10.1364/ol.485913

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