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arXiv · 2003.00420

280-km experimental demonstration of quantum digital signature with one decoy state

Hua-Jian Ding·Jing-Jing Chen·Liang Ji·Xing-Yu Zhou·Chun-Hui Zhang·Chun-Mei Zhang·Qin Wang
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Abstract

Quantum digital signature (QDS) guarantee the unforgeability, nonrepudiation and transferability of signature messages with information-theoretical security, and hence has attracted much attention recently. However, most previous implementations of QDS showed relatively low signature rates or/and short transmission distance. In this paper, we report a proof-of-principle phase-encoding QDS demonstration using only one decoy state. Firstly, such method avoids the modulation of vacuum state, thus reducing experimental complexity and random number consumption. Moreover, incorporating with low-loss asymmetric Mach-Zehnder interferometers and real-time polarization calibration technique, we have successfully achieved higher signature rate, e.g., 0.98 bit/s at 103 km, and to date a record-breaking transmission distance over 280-km installed fibers. Our work represents a significant step towards real-world applications of QDS.

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Hua-Jian Ding, Jing-Jing Chen, Liang Ji, Xing-Yu Zhou, Chun-Hui Zhang, Chun-Mei Zhang, Qin Wang. 2020-03-01. 280-km experimental demonstration of quantum digital signature with one decoy state. https://doi.org/10.1364/ol.389848

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