论文标题
基于时间键入的QKD中的非理想光子检测器的信息率
Information Rates with Non Ideal Photon Detectors in Time-Entanglement Based QKD
论文作者
论文摘要
我们开发了量化光子检测器缺陷对基于时间键入的量子键分布（QKD）的秘密密钥率的影响的新方法。我们解决了光子检测正时抖动，检测器的停机时间和光子黑暗计数，并显示每个人如何以不同的方式降低最大可实现的秘密密钥速度。我们从标准的无内存通道（DMC）模型开始，以对由于定时抖动而丢失的相互信息构成良好的限制，然后引入基于新颖的马尔可夫链（MC）模型，以表征检测器停机时间的效果，并向其向密钥生成过程中引入内存。最后，我们提出了一种在分析中加入黑暗计数的新方法，该方法表明，在使用公共脉冲位置调制（PPM）进行钥匙生成时，黑暗计数如何特别有害。我们的结果表明，这三个缺陷可以显着降低QKD PPM时可实现的秘密密钥率。此外，我们的主要结果之一是为实验者提供工具，以预测其系统可实现的秘密关键率，鉴于检测器规格。
We develop new methods of quantifying the impact of photon detector imperfections on achievable secret key rates in Time-Entanglement based Quantum Key Distribution (QKD). We address photon detection timing jitter, detector downtime, and photon dark counts and show how each may decrease the maximum achievable secret key rate in different ways. We begin with a standard Discrete Memoryless Channel (DMC) model to get a good bound on the mutual information lost due to the timing jitter, then introduce a novel Markov Chain (MC) based model to characterize the effect of detector downtime and show how it introduces memory to the key generation process. Finally, we propose a new method of including dark counts in the analysis that shows how dark counts can be especially detrimental when using the common Pulse Position Modulation (PPM) for key generation. Our results show that these three imperfections can significantly reduce the achievable secret key rate when using PPM for QKD. Additionally, one of our main results is providing tooling for experimentalists to predict their systems' achievable secret key rate given the detector specifications.
