Integrated Optical System for Mobile Atomic Interferometric Gravity Gradient.

This study presents the development of an integrated optical system suitable for mobile atomic interferometry-based gravity gradient measurements. The system exhibits distinct technical advantages, including a simplified frequency-shifting scheme, low laser power consumption, and elimination of mechanical switches. In terms of frequency-shifting design, gravity gradient measurements via atomic interferometry are accomplished using only two frequency shifts at 133 MHz and 400 MHz, which effectively streamlines the optical configuration and significantly reduces the complexity of the supporting radio-frequency (RF) driving system. For power consumption control, a dual-channel fiber laser architecture is adopted, where the total laser power required for atomic interferometry gravity gradient measurements is satisfied with relatively low output power. Furthermore, to meet the laser isolation requirements during measurements, a high-isolation RF driving module is developed, replacing conventional mechanical switches and enabling the integration and miniaturization of the optical system. Using this integrated optical setup, mobile gravity gradient measurement experiments based on atomic interferometry are performed, achieving high-precision mobile atomic interferometric gravity gradient measurement with a long-term stability of 1.08 E (1 E = 10-9 s-2).