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arXiv · 2202.10059

Improving the performance of twin-field quantum key distribution with advantage distillation technology

Hong-Wei Li·Rui-Qiang Wang·Chun-Mei Zhang·Qing-Yu Cai
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Abstract

In this work, we apply the advantage distillation method to improve the performance of a practical twin-field quantum key distribution system under collective attack. Compared with the previous analysis result given by Maeda, Sasaki and Koashi [Nature Communication 10, 3140 (2019)], the maximal transmission distance obtained by our analysis method will be increased from 420 km to 470 km. By increasing the loss-independent misalignment error to 12%, the previous analysis method can not overcome the rate-distance bound. However, our analysis method can still overcome the rate-distance bound when the misalignment error is 16%. More surprisingly, we prove that twin-field quantum key distribution can generate positive secure key even if the misalignment error is close to 50%, thus our analysis method can significantly improve the performance of a practical twin-field quantum key distribution system.

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Hong-Wei Li, Rui-Qiang Wang, Chun-Mei Zhang, Qing-Yu Cai. 2022-02-21. Improving the performance of twin-field quantum key distribution with advantage distillation technology. https://doi.org/10.22331/q-2023-12-06-1201

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