论文标题
源统计对利用光子纠缠中量子键分布的影响
Effect of source statistics on utilizing photon entanglement in quantum key distribution
论文作者
论文摘要
提出了评估纠缠源质量的工作流程。基于从理论模型和实验数据获得的量子状态密度矩阵，我们估算了量子键分布协议中量子纠缠源的潜在性能。展示了此工作流程，用于连续抽水的自发参数下转换（SPDC）源，它突出了由生成的量子状态的多光性质引起的纠缠成对生成速率和纠缠质量之间的权衡。我们采用这种表征技术来表明，由于固有的多光子贡献，向下转换光子对的安全键限制为每个检测窗口的0.029位。我们还报告说，连续波下转换源的最佳增益有一个最佳增益。我们找到了从SPDC来源提取的安全密钥速率的结合，并与完全单对量子状态进行比较，例如量子点产生的量子。
A workflow for evaluation of entanglement source quality is proposed. Based on quantum state density matrices obtained from theoretical models and experimental data, we make an estimate of a potential performance of a quantum entanglement source in quantum key distribution protocols. This workflow is showcased for continuously pumped spontaneous parametric down-conversion (SPDC) source, where it highlights the trade-off between entangled pair generation rate and entanglement quality caused by multiphoton nature of the generated quantum states. We employ this characterization technique to show that secure key rate of down-converted photon pairs is limited to 0.029 bits per detection window due to intrinsic multiphoton contributions. We also report that there exists one optimum gain for continuous-wave down-conversion sources. We find a bound for secure key rate extracted from SPDC sources and make a comparison with perfectly single-pair quantum states, such as those produced by quantum dots.
