论文标题
比较离散变量和连续变量量子键分布方案与热损失通道中的相位噪声的比较
Comparison of Discrete Variable and Continuous Variable Quantum Key Distribution Protocols with Phase Noise in the Thermal-Loss Channel
论文作者
论文摘要
基于单光子检测器和源的离散变量（DV）量子密钥分布（QKD）已成功部署用于长期安全键分布。另一方面，基于相干检测器和来源的连续变量（CV）量子键分布（QKD）目前在损失和噪声耐受性方面落后。 DV-QKD和CV-QKD之间的一个重要辨别因子是相位噪声的效果，该效果在CV-QKD中更为相关。在本文中，我们研究了相位噪声对DV-QKD和CV-QKD协议的影响，包括六态协议和挤压状态协议，在热损失通道中，但假定可用性的完美源和检测器。我们发现，与DV-QKD相比，CV-QKD在低相位噪声方面，但是CV-QKD可以忍受更多的损失。我们还将秘密关键率视为QKD性能的额外指标。该数量高的要求大大扩展了CV-QKD的性能要比DV-QKD更好的区域。我们的分析解决了相位噪声如何影响DV-QKD和CV-QKD的问题，以及为什么前者在热损失通道中表现更好。
Discrete-variable (DV) quantum key distribution (QKD) based on single-photon detectors and sources have been successfully deployed for long-range secure key distribution. On the other hand, continuous-variable (CV) quantum key distribution (QKD) based on coherent detectors and sources is currently lagging behind in terms of loss and noise tolerance. An important discerning factor between DV-QKD and CV-QKD is the effect of phase noise, which is known to be more relevant in CV-QKD. In this article, we investigate the effect of phase noise on DV-QKD and CV-QKD protocols, including the six-state protocol and squeezed-state protocol, in a thermal-loss channel but with the assumed availability of perfect sources and detectors. We find that in the low phase noise regime but high thermal noise regime, CV-QKD can tolerate more loss compared to DV-QKD. We also compare the secret key rate as an additional metric for the performance of QKD. Requirements for this quantity to be high vastly extend the regions at which CV-QKD performs better than DV-QKD. Our analysis addresses the questions of how phase noise affects DV-QKD and CV-QKD and why the former has historically performed better in a thermal-loss channel.
