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arXiv · 2504.19242

Experimental Multi-Dimensional Side-Channel-Secure Quantum Key Distribution

Hao Dong·Cong Jiang·Di Ma·Chi Zhang·Jia Huang·Hao Li·Li-Xing You·Yang Liu·Xiang-Bin Wang·Qiang Zhang·Jian-Wei Pan
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Abstract

Quantum key distribution (QKD) theoretically provides unconditional security between remote parties. However, guaranteeing practical security through device characterisation alone is challenging in real-world implementations due to the multi-dimensional spaces in which the devices may be operated. The side-channel-secure (SCS)-QKD protocol, which only requires bounding the upper limits of the intensities for the two states, theoretically provides a rigorous solution to the challenge and achieves measurement-device-independent security in detection and security for whatever multi-dimensional side channel attack in the source. Here, we demonstrate a practical implementation of SCS-QKD, achieving a secure key rate of $6.60$ kbps through a 50.5 km fibre and a maximum distribution distance of 101.1 km while accounting for finite-size effects. Our experiment also represents an approximate forty-times improvement over the previous experiment.

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Hao Dong, Cong Jiang, Di Ma, Chi Zhang, Jia Huang, Hao Li, Li-Xing You, Yang Liu, Xiang-Bin Wang, Qiang Zhang, Jian-Wei Pan. 2025-04-27. Experimental Multi-Dimensional Side-Channel-Secure Quantum Key Distribution. https://arxiv.org/abs/2504.19242

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