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arXiv · 2105.09587

Experimental measurement-device-independent quantum key distribution with the double-scanning method

Yi-Peng Chen·Jing-Yang Liu·Mingshuo Sun·Xing-Xu Zhou·Chun-Hui Zhang·Jian Li·Qin Wang
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Abstract

The measurement-device-independent quantum key distribution (MDI-QKD) can be immune to all detector side-channel attacks. Moreover, it can be easily implemented combining with the matured decoy-state methods under current technology. It thus seems a very promising candidate in practical implementation of quantum communications. However, it suffers from severe finite-data-size effect in most existing MDI-QKD protocols, resulting in relatively low key rates. Recently, Jiang et al. [Phys. Rev. A 103, 012402 (2021)] proposed a double-scanning method to drastically increase the key rate of MDI-QKD. Based on Jiang et al.'s theoretical work, here we for the first time implement the double-scanning method into MDI-QKD and carry out corresponding experimental demonstration. With a moderate number of pulses of 10^10, we can achieve 150 km secure transmission distance which is impossible with all former methods. Therefore, our present work paves the way towards practical implementation of MDI-QKD.

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Yi-Peng Chen, Jing-Yang Liu, Mingshuo Sun, Xing-Xu Zhou, Chun-Hui Zhang, Jian Li, Qin Wang. 2021-05-20. Experimental measurement-device-independent quantum key distribution with the double-scanning method. https://doi.org/10.1364/ol.431061

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