Optical system for a strontium optical lattice clock aboard the Chinese Space Station

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.