Modular-assembled laser system for a long-baseline atom interferometer

The Zhaoshan long-baseline Atom Interferometer Gravitation Antenna (ZAIGA) is a new, to the best of our knowledge, type of large-scale atom interferometer facility under construction for the study of gravitation and related problems. To meet the different requirements of the laser system for the atom interferometer using various atoms (including ⁸⁵Rb, ⁸⁷Rb, ⁸⁷Sr, and ⁸⁸Sr), we design and implement a modular assembled laser system. By dividing the laser system into different basic units according to their functions and modularizing each unit, the laser system is made highly scalable while being compact and stable. Its intensity stability is better than 0.1% in 10²s and 0.5% in 10⁴s. We test the performance of the laser system with two experimental systems, i.e., an ⁸⁵Rb-⁸⁷Rb dual-species ultracold atom source and an ⁸⁵Rb atom interferometer. The ⁸⁵Rb-⁸⁷Rb dual-species magneto-optical trap and the ⁸⁵Rb atom interference fringes are realized by using this laser system, indicating that its technical performance can meet the major experimental requirements.