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Overcoming the Rate-Loss Limit without Global Phase Tracking

Lai Zhou, Jinping Lin, Yuan-Mei Xie, Yu-Shuo Lu, Yumang Jing, Hua‐Lei Yin, Zhiliang L. Yuan

Published Jan 1, 2023• 0 citations
Publisher

Abstract

We achieve a finite-size key rate of 42.64bps over 508km fibers, breaking the fundamental rate-loss limit of point-point quantum key distribution (QKD), via implementing an innovative measurement-device-independent QKD through asynchronous coincidence pairing.
DOI
10.1364/cleo_fs.2023.ff2a.6

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Quantum key distribution (QKD) allows users to generate shared encryption keys that are guaranteed to be theoretically secure by the laws of quantum mechanics. Most implementations use light pulses that are attenuated by the propagation medium. This leads to a fundamental rate-distance limit in QKD that was thought to be impossible to overcome with current technology. The recent proposal of "Twin-Field QKD", however, changed this belief and showed how to overcome this limit and perform long-distance QKD with present-day technology. In my talk I will review the most significant theoretical and experimental results in this emerging and rapidly growing research area.
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