标题： 固态微瓦输出功率的微波放大器在中等低温温度下 显示英文标题

标题： Solid-State Maser with Microwatt Output Power at Moderate Cryogenic Temperatures

摘要： 固态磁泵由于其极低的噪声温度，被独特地定位为超低相位噪声微波源。然而，由于输出功率低和需要深度低温冷却，其实际应用一直受到历史限制。在本工作中，我们提出了一种新型的连续波金刚石基磁泵振荡器，工作在约14.5 GHz和中等低温（约180 K），实现了超过-30 dBm（1微瓦）的输出功率水平。这种性能比之前的金刚石或红宝石基磁泵振荡器提高了两个数量级。我们的系统集成了一个高-Q（约2460）的紧凑金属微波腔体和光学泵浦的（111）取向NV丰富的金刚石晶体。该腔体支持高效的光耦合和热耗散，使用成本效益高的绿色LED可以实现持续的高功率光学激发（>1 W）。我们展示了稳定的磁泵运行，具有良好的频谱质量，并通过频率域和时间域分析以及在“自由运行”模式下操作时的相位噪声数据验证了其输出。此外，我们基于Leeson模型提供了相位噪声估计，并表明当耦合到高-Q外部谐振器时，这样的磁泵可能接近热限制的相位噪声水平。这些预测表明，考虑到其能够使用坚固的、无氦的斯特林冷却器在较高温度下运行，金刚石磁泵有很强的潜力超越传统的红宝石基或其他类似磁泵系统。尽管目前在频率稳定性和抖动方面存在局限性，但这项工作确立了基于金刚石的磁泵作为下一代超低相位噪声微波振荡器的有希望的候选者。进一步的工程优化——特别是场稳定性、热调节和反馈锁定——将是释放其全部潜力的关键。 显示英文摘要

摘要： Solid-state masers are uniquely positioned to serve as ultra-low phase noise microwave sources due to their exceptionally low noise temperatures. However, their practical application has been historically limited by low output power and the need for deep cryogenic cooling. In this work, we present a novel design for a continuous-wave diamond-based maser oscillator operating at about 14.5 GHz and moderate cryogenic temperatures (about 180 K), achieving output power levels exceeding -30 dBm (1 microW). This performance represents a two-orders-of-magnitude improvement over previous diamond or ruby-based maser oscillators.Our system integrates a high-Q (about 2460) compact metallic microwave cavity with optically pumped (111)-oriented NV-rich diamond crystals. The cavity supports efficient light coupling and thermal dissipation, enabling sustained high-power optical excitation (>1 W) using cost-effective green LEDs. We demonstrate stable maser operation with good spectral quality and validate its output through both frequency- and time-domain analysis with phase noise data when operated in "free running" mode. Additionally, we provide phase noise estimations based on Leeson's model and show that, when coupled to a high-Q external resonator, such masers could approach thermally limited phase noise levels. These predictions suggest strong potential for diamond masers to outperform traditional ruby-based or similar maser systems, especially given their ability to operate at higher temperatures using rugged, He-free Stirling coolers. Despite current limitations related to frequency stability and jitter, this work establishes diamond-based masers as promising candidates for next-generation ultra-low phase noise microwave oscillators. Further engineering optimization - particularly in field stability, thermal regulation, and feedback locking - will be key to unlocking their full potential.