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arXiv · 2407.16432

Integrated high-performance error correction for continuous-variable quantum key distribution

Chuang Zhou·Yang Li·Li Ma·Jie Yang·Wei Huang·Ao Sun·Heng Wang·Yujie Luo·Yong Li·Ziyang Chen·Francis C. M. Lau·Yichen Zhang·Song Yu·Hong Guo·Bingjie Xu
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Abstract

An integrated error-correction scheme with high throughput, low frame errors rate (FER) and high reconciliation efficiency under low signal to noise ratio (SNR) is one of the major bottlenecks to realize high-performance and low-cost continuous variable quantum key distribution (CV-QKD). To solve this long-standing problem, a novel two-stage error correction method with limited precision that is suitable for integration given limited on-chip hardware resource while maintaining excellent decoding performance is proposed, and experimentally verified on a commercial FPGA. Compared to state-of-art results, the error-correction throughput can be improved more than one order of magnitude given FER<0.1 based on the proposed method, where 544.03 Mbps and 393.33 Mbps real-time error correction is achieved for typical 0.2 and 0.1 code rate, respectively. Besides, compared with traditional decoding method, the secure key rate (SKR) for CV-QKD under composable security framework can be improved by 140.09% and 122.03% by using the proposed two-stage decoding method for codes rate 0.2 and 0.1, which can support 32.70 Mbps and 5.66 Mbps real-time SKR under typical transmission distances of 25 km and 50 km, correspondingly. The record-breaking results paves the way for large-scale deployment of high-rate integrated CV-QKD systems in metropolitan quantum secure network.

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Chuang Zhou, Yang Li, Li Ma, Jie Yang, Wei Huang, Ao Sun, Heng Wang, Yujie Luo, Yong Li, Ziyang Chen, Francis C. M. Lau, Yichen Zhang, Song Yu, Hong Guo, Bingjie Xu. 2024-07-23. Integrated high-performance error correction for continuous-variable quantum key distribution. https://arxiv.org/abs/2407.16432

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