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arXiv · 2103.06058

Experimental Side-Channel-Free Quantum Key Distribution

Chi Zhang·Xiao-Long Hu·Jiu-Peng Chen·Yang Liu·Weijun Zhang·Zong-Wen Yu·Hao Li·Lixing You·Zhen Wang·Xiang-Bin Wang·Qiang Zhang·Jian-Wei Pan
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Abstract

Quantum key distribution can provide unconditionally secure key exchange for remote users in theory. In practice, however, in most quantum key distribution systems, quantum hackers might steal the secure keys by listening to the side channels in the source, such as the photon frequency spectrum, emission time, propagation direction, spatial angular momentum, and so on. It is hard to prevent such kinds of attacks because side channels may exist in any of the encoding space whether the designers take care of or not. Here we report an experimental realization of a side-channel-free quantum key distribution protocol which is not only measurement-device-independent, but also immune to all side-channel attacks in the source. We achieve a secure key rate of 4.80e-7 per pulse through 50 km fiber spools.

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Chi Zhang, Xiao-Long Hu, Jiu-Peng Chen, Yang Liu, Weijun Zhang, Zong-Wen Yu, Hao Li, Lixing You, Zhen Wang, Xiang-Bin Wang, Qiang Zhang, Jian-Wei Pan. 2021-03-10. Experimental Side-Channel-Free Quantum Key Distribution. https://doi.org/10.1103/physrevlett.128.190503

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