1207.1473 (Xiongfeng Ma et al.)

Postprocessing for quantum random number generators: entropy evaluation
and randomness extraction    [PDF]

Xiongfeng Ma, Feihu Xu, He Xu, Xiaoqing Tan, Bing Qi, Hoi-Kwong Lo

A quantum random number generator (QRNG) can offer means to generate information-theoretically provable random numbers in principle. Unfortunately, in practice, the quantum randomness is inevitably mixed with classical noises. To distill the quantum randomness, one needs to quantify the randomness of the source and then apply a randomness extractor. Here, we propose a framework for evaluating quantum randomness of a physical device by min-entropy. In our post-processing, we implement two information-theoretically provable extractors -- Toeplitz-hashing extractor and Trevisan's extractor -- that yield a speed of 441 kb/s and 0.7 kb/s, respectively. The outcomes from both extractors pass all the standard randomness tests we exploited. It is the first time that such extractors are proposed and implemented in QRNG.

View original: http://arxiv.org/abs/1207.1473