Experimental Realization of Device-Independent Quantum Randomness Expansion
Minghan Li, Xingjian Zhang, Wen‐Zhao Liu, Si-Ran Zhao, Bing Bai, Yang Liu, Qi Zhao, Yuxiang Peng, Jun Zhang, Yanbao Zhang, W. J. Munro, Xiongfeng Ma, Qiang Zhang, Jingyun Fan, Jian-Wei Pan
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 $5.47\ifmmode\times\else\texttimes\fi{}{10}^{8}$ quantum-proof random bits while consuming $4.39\ifmmode\times\else\texttimes\fi{}{10}^{8}\text{ }\text{ }\mathrm{bits}$ of entropy, expanding our store of randomness by $1.08\ifmmode\times\else\texttimes\fi{}{10}^{8}\text{ }\text{ }\mathrm{bits}$ at a latency of about 13.1 h, with a total soundness error $4.6\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}10}$. 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.