Masers once represented the state of the art in low-noise microwave amplification technology but eventually became obsolete due to their need for cryogenic cooling. Masers based on solid-state spin systems perform most effectively as amplifiers, since they provide a large density of spins and can, therefore, operate at relatively high powers. While solid-state maser oscillators have been demonstrated at room temperature, continuous-wave amplification in these systems has only ever been realized at cryogenic temperatures. Here, we report on a continuous-wave solid-state maser amplifier operating at room temperature. We achieve this feat using a practical setup that includes an ensemble of nitrogen-vacancy center spins in a diamond crystal, a strong permanent magnet, and a simple laser diode. We describe important amplifier characteristics including gain, bandwidth, compression power, and noise temperature and discuss the prospects of realizing a room-temperature near-quantum-noise-limited amplifier with this system. Finally, we show that in a different mode of operation the spins can be used to reduce the microwave noise in an external circuit to cryogenic levels, all without the requirement for physical cooling. Published by the American Physical Society 2024

中文翻译：

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室温固态 Maser 放大器


Maser 曾经代表了低噪声微波放大技术的最新技术，但由于需要低温冷却，最终过时了。基于固态自旋系统的 Maser 作为放大器的性能最有效，因为它们提供大自旋密度，因此可以在相对较高的功率下运行。虽然固态 maser 振荡器已在室温下得到证明，但这些系统中的连续波放大仅在低温下实现。在这里，我们报告了在室温下运行的连续波固态 maser 放大器。我们使用一种实用的装置实现了这一壮举，其中包括金刚石晶体中的氮空位中心旋转集合、强永磁体和简单的半导体激光管。我们描述了重要的放大器特性，包括增益、带宽、压缩功率和噪声温度，并讨论了使用该系统实现室温近量子噪声限制放大器的前景。最后，我们表明，在不同的工作模式下，自旋可用于将外部电路中的微波噪声降低到低温水平，所有这些都不需要物理冷却。 美国物理学会 2024 年出版