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arXiv · 1604.01915

More randomness from a prepare-and-measure scenario with independent devices

Han Yun-Guang·Yin Zhen-Qiang·Li Hong-Wei·Chen Wei·Wang Shuang·Guo Guang-Can·Han Zheng-Fu
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Abstract

How to generate genuine quantum randomness from untrusted devices is an important problem in quantum information processing. Inspired by previous work on a self-testing quantum random number generator [T. Lunghi et al., Phys. Rev. Lett. 114, 150501 (2015)], we present a method to generate quantum randomness from a prepare-and-measure scenario with independent devices. In existing protocols, the quantum randomness depends only on a witness value (e.g., Clauser-Horne-Shimony-Holt value), which is calculated with the observed probabilities. Differently, here all the observed probabilities are directly used to calculate the min-entropy in our method. Through numerical simulation, we find that the min-entropy of our proposed scheme is higher than that in the previous work when a typical untrusted Bennett-Brassard 1984 (BB84) setup is used. Consequently, thanks to the proposed method, more genuine quantum random numbers may be obtained than before.

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Han Yun-Guang, Yin Zhen-Qiang, Li Hong-Wei, Chen Wei, Wang Shuang, Guo Guang-Can, Han Zheng-Fu. 2016-04-07. More randomness from a prepare-and-measure scenario with independent devices. https://doi.org/10.1103/physreva.93.032332

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