arXiv:2207.08345

Secure bound analysis of quantum key distribution with non-uniform random seed of privacy amplification

Bingze Yan, Yucheng Qiao, Qiong Li, Haokun Mao

Published Jul 18, 2022• 0 citations

Abstract

Precise quantum key distribution (QKD) secure bound analysis is essential for practical QKD systems. The effect of uniformity of random number seed for privacy amplification is not considered in existing secure bound analysis. In this paper, we propose and prove the quantum leftover hash lemma with non-uniform random number seeds based on the min-entropy, and we give a precise QKD secure bound analysis with non-uniform random number seeds on this basis. We take the two-decoy BB84 protocol as an example to simulate the effect of random number seed uniformity on the secure bound of a QKD system. The experimental results indicate that when the average min-entropy of the random number generator is below 0.95, the secure bound of a QKD system will be seriously affected.

DOI: 10.48550/arxiv.2207.08345

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