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Applied Optics

Highly reliable optical system for a rubidium space cold atom clock

Wei Ren, Yanguang Sun, Bin Wang, Wenbing Xia, Qiuzhi Qu, Jingfeng Xiang, Zuoren Dong, Desheng Lü, Liang Liu

Published Apr 27, 2016• 23 citations
Publisher

Abstract

We describe a highly reliable optical system designed for a rubidium space cold atom clock (SCAC), presenting its design, key technologies, and optical components. All of the optical and electronic components are integrated onto an optimized two-sided 300 mm×290 mm×30 mm optical bench. The compact optical structure and special thermal design ensure that the optical system can pass all of the space environmental qualification tests including both thermal vacuum and mechanical tests. To verify its performance, the optical system is carefully checked before and after each test. The results indicate that this optical system is suitably robust for the space applications for which the rubidium SCAC was built.

DOI
10.1364/ao.55.003607

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We report the design and in-orbit demonstration of a compact optical system for a 87Sr optical lattice clock aboard the Chinese Space Station. This system adopts a compact and robust vertically stacked architecture with a total volume of 0.11 m3 and a mass of 53.6 kg. It passed thermal and vibration qualification tests and remained fully operational after launch. In orbit, it achieved automated multi-stage laser stabilization and a blue magneto-optical trap for 87Sr atoms. This marks a significant step toward operational optical clocks in space.