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arXiv · 2205.05527

Sending-or-Not-Sending Twin-Field Quantum Key Distribution with Redundant Space

Hai Xu·Xiao-Long Hu·Cong Jiang·Zong-Wen Yu·Xiang-Bin Wang
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Abstract

We propose to adopt redundant space such as polarization mode in the sending-or-not-sending Twin-Field quantum key distribution (TF-QKD) in the Fock space. With the help of redundant space such as photon polarization, we can post-select events according to the outcome of the observation to the additional quantity. This compresses the bit-flip error rate in the post-selected events of the SNS protocol. The calculation shows that the method using redundant space can greatly improve the performance in practical TF-QKD, especially when the total number of pulses is small.

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Hai Xu, Xiao-Long Hu, Cong Jiang, Zong-Wen Yu, Xiang-Bin Wang. 2022-05-11. Sending-or-Not-Sending Twin-Field Quantum Key Distribution with Redundant Space. https://arxiv.org/abs/2205.05527

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