Miniature Laser Frequency Stabilisation Module for Cold Atom Sensing

a miniature laser frequency stabilization module for cold-atom sensing applications is designed and realized, which can lock the laser frequency to the saturated absorption spectrum of the D2 line of rubidium atoms through the Pound-Drever-Hall technique. The core of the module is a tiny rubidium gas cell, which is co-packaged with the saturation absorption optical setup, temperature control circuit, and detection circuit through the joint optical-mechanical-electrical design, with a total volume of only 40×15×30 mm3. The frequency fluctuation of the 780 nm laser after frequency stabilization by the module is within 4.7 MHz in 1400 s, which can be used for cold-atom production experiments. The results verify the feasibility of the module as a frequency reference and provide a solution of light source for portable cold atom sensing devices.