Compact modulation transfer spectroscopy module for highly stable laser frequency

A compact modulation transfer spectroscopy (CMTS) module with high stability in frequency and robustness is realized for a transportable 87Rb atomic gravimeter. The module is fabricated in a 91 mm×169 mm×60 mm box. The frequency instability achieved with CMTS is below 1.3×10−13/τ in the short term, not exceeding 5×10−12 until 1×105s, which is the best performance of 87Rb recorded so far in the literature. The achievement of high frequency stability with CMTS is discussed, analyzing the factors that impact frequency stability, with the Allan deviation measured under various conditions. This study offers a novel and efficient choice for applications employing the stabilized laser frequency and transportable system.