Institut für Theoretische Physik, Leibniz Universität Hannover, Hannover, Germany.
Phys Rev Lett. 2012 Sep 7;109(10):100502. doi: 10.1103/PhysRevLett.109.100502. Epub 2012 Sep 5.
We provide a security analysis for continuous variable quantum key distribution protocols based on the transmission of two-mode squeezed vacuum states measured via homodyne detection. We employ a version of the entropic uncertainty relation for smooth entropies to give a lower bound on the number of secret bits which can be extracted from a finite number of runs of the protocol. This bound is valid under general coherent attacks, and gives rise to keys which are composably secure. For comparison, we also give a lower bound valid under the assumption of collective attacks. For both scenarios, we find positive key rates using experimental parameters reachable today.
我们提供了一种基于相干态光场的连续变量量子密钥分发协议的安全性分析。我们利用光滑熵的熵不确定性关系得到了一个下界，用于确定从协议的有限次运行中提取的秘密比特数。该下界在一般相干攻击下是有效的，并产生可组合安全的密钥。作为比较，我们还给出了在集体攻击假设下有效的下界。对于这两种情况，我们使用当前可达到的实验参数找到了正的密钥率。
