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arXiv · 1109.0643

Ultrafast quantum random number generation based on quantum phase fluctuations

Feihu Xu·Bing Qi·Xiongfeng Ma·He Xu·Haoxuan Zheng·Hoi-Kwong Lo
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Abstract

A quantum random number generator (QRNG) can generate true randomness by exploiting the fundamental indeterminism of quantum mechanics. Most approaches to QRNG employ single-photon detection technologies and are limited in speed. Here, we propose and experimentally demonstrate an ultrafast QRNG at a rate over 6 Gb/s based on the quantum phase fluctuations of a laser operating near threshold. Moreover, we consider a potential adversary who has partial knowledge on the raw data and discuss how one can rigorously remove such partial knowledge with post-processing. We quantify the quantum randomness through min-entropy by modeling our system, and employ two extractors, Trevisan's extractor and Toeplitz-hashing, to distill the randomness, which is information-theoretically provable. The simplicity and high-speed of our experimental setup show the feasibility of a robust, low-cost, high-speed QRNG.

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Feihu Xu, Bing Qi, Xiongfeng Ma, He Xu, Haoxuan Zheng, Hoi-Kwong Lo. 2011-09-03. Ultrafast quantum random number generation based on quantum phase fluctuations. https://doi.org/10.1364/oe.20.012366

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