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arXiv · 1811.01263

Encoding-side-channel-free and measurement-device-independent quantum key distribution

Xiang-Bin Wang·Xiao-Long Hu·Zong-Wen Yu
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Abstract

We present a simple protocol where Alice and Bob only needs sending out a coherent state or not-sending out a coherent state to Charlie. There is no bases switching. We show that this protocol is both encoding-state-side-channel free to the source part and measurement-device-independent. We don't have to control exactly the whole space state of the light pulse, which is an impossible task in practice. The protocol is immune to all adverse due to encoding-state imperfections in side-channel space such as the photon frequency spectrum, emission time, propagation direction, spatial angular moment, and so on. Numerical simulation shows that our scheme can reach a side-channel-free result for quantum key distribution over a distance longer than 200 km given the single-photon-interference misalignment error rate of $20\%$.

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Xiang-Bin Wang, Xiao-Long Hu, Zong-Wen Yu. 2018-11-03. Encoding-side-channel-free and measurement-device-independent quantum key distribution. https://doi.org/10.1103/physrevapplied.12.054034

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