Quantum-limited microwave parametric amplifiers are genuine key pillars for rising quantum technologies and, in general, for applications that rely on the successful readout of weak microwave signals by adding only the minimum amount of noise allowed by quantum mechanics. In this Perspective, after providing a brief overview on the different families of parametric microwave amplifiers, we focus on traveling wave parametric amplifiers, underlining the key achievements of the last few years and the present open challenges. We also discuss possible new research directions beyond amplification such as exploring these devices as a platform for multi-mode entanglement generation and for the development of single photon detectors.

中文翻译：

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行波微波参量放大器展望

量子限制微波参量放大器是新兴量子技术的真正关键支柱，一般来说，对于依赖于通过仅添加量子力学允许的最少量噪声来成功读取微弱微波信号的应用。在本展望中，在简要概述不同系列的参量微波放大器之后，我们将重点介绍行波参量放大器，强调过去几年的主要成就和当前面临的挑战。我们还讨论了除放大之外可能的新研究方向，例如探索这些设备作为多模式纠缠生成和单光子探测器开发的平台。