Miniaturized optical system for high-precision mobile atomic gravimeters

Inertial sensors utilizing cold atom interferometry are advancing toward real-world applications, necessitating optical systems with superior integration and stability. We have developed a highly integrated and stable optical system for a fountain-type Rb atom gravimeter, utilizing dual fiber laser outputs to generate all the laser beams. The optical system design involves bonding miniaturized optical components onto quartz glass plates, significantly reducing the volume of the optical module while maintaining high spatial laser utilization efficiency. This enables the system to be integrated into a chassis with the dimension of 43 cm × 42 cm × 13 cm. Remarkably, the system maintains its functionality without the need for adjustments even after being transported over 14,000 km. It achieves a gravity measurement sensitivity of 14.5 µGal/Hz and a long-term stability of 0.4 µGal over 2560 seconds. This versatile optical system also supports various atom interferometry-based sensors, facilitating their deployment in practical settings.