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arXiv · 2308.13154

Qubit-based distributed frame synchronization for quantum key distribution

Ye Chen·Chunfeng Huang·Shuyi Huang·Zhenrong Zhang·Kejin Wei
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Abstract

Quantum key distribution (QKD) is a method that enables two remote parties to share a secure key string. Clock synchronization between two parties is a crucial step in the normal operation of QKD. Qubit-based synchronization can achieve clock synchronization by transmitting quantum states between two remote parties, eliminating the necessity for hardware synchronization and thereby greatly reducing the hardware requirements of a QKD system. Nonetheless, classical qubit-based synchronization exhibits poor performance in continuous and high-loss systems, hindering its wide applicability in various scenarios. We propose a qubit-based distributed frame synchronization method that can achieve time recovery in a continuously running system and resist higher losses. Experimental results show that the proposed method outperforms the advanced qubit-based synchronization method Qubit4Sync in a continuously running system. We believe our method is applicable to a broad range of QKD scenarios, including drone-based QKD and quantum network construction.

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Ye Chen, Chunfeng Huang, Shuyi Huang, Zhenrong Zhang, Kejin Wei. 2023-08-25. Qubit-based distributed frame synchronization for quantum key distribution. https://arxiv.org/abs/2308.13154

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