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arXiv · 1408.2884

Measurement-device-independent quantum key distribution with all-photonic adaptive Bell measurement

Koji Azuma·Kiyoshi Tamaki·William J. Munro
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Abstract

The time-reversed version of entanglement-based quantum key distribution (QKD), called measurement-device-independent QKD (mdiQKD), was originally introduced to close arbitrary security loopholes of measurement devices. Here we show that the mdiQKD has another advantage which should be distinguished from the entanglement-based QKD. In particular, an all-photonic adaptive Bell measurement, based on the concept of quantum repeaters, can be installed solely in the mdiQKD, which leads to a square root improvement in the key rate. This Bell measurement also provides a similar improvement in the single-photon-based entanglement generation of quantum repeaters.

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Koji Azuma, Kiyoshi Tamaki, William J. Munro. 2014-08-13. Measurement-device-independent quantum key distribution with all-photonic adaptive Bell measurement. https://arxiv.org/abs/1408.2884

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