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arXiv · 1902.07529

Experimental Realization of Device-Independent Quantum Randomness Expansion

Ming-Han Li·Xingjian Zhang·Wen-Zhao Liu·Si-Ran Zhao·Bing Bai·Yang Liu·Qi Zhao·Yuxiang Peng·Jun Zhang·Yanbao Zhang·William J. Munro·Xiongfeng Ma·Qiang Zhang·Jingyun Fan·Jian-Wei Pan
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Abstract

Randomness expansion where one generates a longer sequence of random numbers from a short one is viable in quantum mechanics but not allowed classically. Device-independent quantum randomness expansion provides a randomness resource of the highest security level. Here, we report the first experimental realization of device-independent quantum randomness expansion secure against quantum side information established through quantum probability estimation. We generate $5.47\times10^8$ quantum-proof random bits while consuming $4.39\times10^8$ bits of entropy, expanding our store of randomness by $1.08\times10^8$ bits at a latency of about $13.1$ h, with a total soundness error $4.6\times10^{-10}$. Device-independent quantum randomness expansion not only enriches our understanding of randomness but also sets a solid base to bring quantum-certifiable random bits into realistic applications.

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Ming-Han Li, Xingjian Zhang, Wen-Zhao Liu, Si-Ran Zhao, Bing Bai, Yang Liu, Qi Zhao, Yuxiang Peng, Jun Zhang, Yanbao Zhang, William J. Munro, Xiongfeng Ma, Qiang Zhang, Jingyun Fan, Jian-Wei Pan. 2019-02-20. Experimental Realization of Device-Independent Quantum Randomness Expansion. https://doi.org/10.1103/physrevlett.126.050503

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