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arXiv · 2107.07803

Measurement-device-independent quantum key distribution with insecure sources

Hua-Jian Ding·Xing-Yu Zhou·Chun-Hui Zhang·Jian Li·Qin Wang
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Abstract

Measurement-device-independent quantum key distribution (MDI-QKD) can eliminate all detector side-channel loopholes and has shown excellent performance in long-distance secret keys sharing. Conventional security proofs, however, require additional assumptions on sources and that can be compromised through uncharacterized side channels in practice. Here, we present a general formalism based on reference technique to prove the security of MDI-QKD against any possible sources imperfection and/or side channels. With this formalism, we investigate the asymptotic performance of single-photon sources without any extra assumptions on the state preparations. Our results highlight the importance of transmitters' security.

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Hua-Jian Ding, Xing-Yu Zhou, Chun-Hui Zhang, Jian Li, Qin Wang. 2021-07-16. Measurement-device-independent quantum key distribution with insecure sources. https://doi.org/10.1364/ol.447234

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