Abstract
We experimentally demonstrated a sub-Mbps key rate Gaussian-modulated coherent-state (GMCS) continuous-variable quantum key distribution (CV-QKD) over a 100-km transmission distance. To efficiently control the excess noise, the quantum signal and the pilot tone are co-transmitted in the fiber channel based on wideband 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 calculated to be 7.55 Mbps, 1.87 Mbps, and 0.51 Mbps over a transmission distance of 50 km, 75 km, and 100 km, respectively. The experimentally demonstrated that the CV-QKD system significantly improves the 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.
© 2023 Optica Publishing Group
Full Article | PDF ArticleMore Like This
Yan Pan, Heng Wang, Yun Shao, Yaodi Pi, Yang Li, Bin Liu, Wei Huang, and Bingjie Xu
Opt. Lett. 47(13) 3307-3310 (2022)
Zikang Su, Dajian Cai, Hao Jiang, Jintao Wang, Dawei Wang, Xiaojie Guo, and Zhaohui Li
Opt. Lett. 47(5) 1287-1290 (2022)
Yan Tian, Yu Zhang, Shuaishuai Liu, Pu Wang, Zhenguo Lu, Xuyang Wang, and Yongmin Li
Opt. Lett. 48(11) 2953-2956 (2023)