Quantum key distribution (QKD) is a swiftly advancing field with the great potential to be ubiquitously adopted in quantum communication applications, attributed to its unique capability to offer ultimate end-to-end theoretical security. However, when transitioning QKD from theory to practice, environmental noise presents a significant impediment, often undermining the real-time efficacy of secure key rates. To uphold the operation of QKD systems, a myriad of protocols and experimental designs have been proposed to counteract the effects of noises. Even with real-time variations, the primary component of environmental noise can be modeled as a unitary evolution or background noise, which can be compensated or reduced with various noise-reducing schemes. This review provides an overview of design strategies for reducing noises in practical QKD systems under various circumstances. These strategies are evaluated based on their principles and suitability in real-world applications. Through this review, we aim to provide readers with a clear understanding of the logic behind these noise-reducing QKD designs, facilitating a smoother start of research and engineering in this field.

中文翻译：

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降噪量子密钥分发


量子密钥分发 （QKD） 是一个快速发展的领域，由于其提供终极端到端理论安全性的独特能力，具有在量子通信应用中无处不在的巨大潜力。然而，当 QKD 从理论过渡到实践时，环境噪声是一个重大障碍，往往会破坏安全密钥速率的实时有效性。为了维持 QKD 系统的运行，已经提出了无数的协议和实验设计来抵消噪声的影响。即使具有实时变化，环境噪声的主要成分也可以建模为幺正演变或背景噪声，这可以通过各种降噪方案进行补偿或减少。本文概述了在各种情况下降低实际 QKD 系统中噪声的设计策略。这些策略根据其原则和在实际应用中的适用性进行评估。通过这篇综述，我们旨在让读者清楚地了解这些降噪 QKD 设计背后的逻辑，从而促进该领域的研究和工程更顺利地开始。