Miniaturized Optical System for a Caesium Satellite-Borne Cold Atom Clock

We present a highly stable and miniaturised optical system designed for a caesium satellite-borne cold atom clock (CSCAC). The optical system was integrated on a 224\,{\mathop{\rm mm}\nolimits} \times 195\,{\mathop{\rm mm}\nolimits} \times 112\,{\mathop{\rm mm}\nolimits} aluminium-based silicon carbide bench and emitted laser beams with four different frequencies on three fiber ports to capture, cool, prepare, and detect atoms. The optical system, utilizing a compact three-layer optical-mechanical and thermal management design, passed environmental simulation tests and adapted to a special satellite-borne environment. The optical system stability meets the laser requirements of the clock.