Space-borne optical frequency references based on spectroscopy of atomic vapors may serve as an integral part of compact optical atomic clocks, which can advance global navigation systems or can be utilized for earth observation missions as part of laser systems for cold atom gradiometers. Nanosatellites offer low launch costs, multiple deployment opportunities, and short payload development cycles, enabling rapid maturation of optical frequency references and underlying key technologies in space. Toward an in-orbit demonstration on such a platform, we have developed a CubeSat-compatible prototype of an optical frequency reference based on the D2 transition in rubidium. A frequency instability of $1.7 \times {10^{- 12}}$ at 1 s averaging time is achieved. The optical module occupies a volume of $35\;{\rm{cm}}^3$, weighs 73 g, and consumes 780 mW of power.

中文翻译：

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用于在纳米卫星上运行的紧凑型基于铷的光学频率基准的原型

基于原子蒸气光谱的星载光学频率参考可以作为紧凑型光学原子钟的组成部分，可以推进全球导航系统，也可以作为冷原子梯度仪激光系统的一部分用于地球观测任务。纳米卫星提供低发射成本、多种部署机会和较短的有效载荷开发周期，使光学频率参考和空间基础关键技术快速成熟。为了在这样的平台上进行在轨演示，我们开发了一个基于铷 D2 跃迁的与 CubeSat 兼容的光频参考原型。在 1 s 平均时间实现了$1.7 \times {10^{- 12}}$的频率不稳定性。光模块占用体积$35\;{\rm{cm}}^3$，重 73 g，消耗 780 mW 功率。