Realization of single optical frequency laser system for optically pumped cesium beam frequency standards

摘要

Compact laser system for optically pumped cesium beam clocks, which use single optical frequency laser for both Cs atomic state preparation and detection, is presented. The saturation probe laser intensity corresponding to certain Cs flux is researched by using laser, locked in the F = 4 → F′= 4 transition of the Cs D_2 line, to interact with Cs atoms. Light shift produced by laser could be reduced when the laser with small intensity, 0.7 mw/cm~2, is used to interact with Cs atoms. High efficiency, 70%, fluorescence collectors are installed in the atom-laser interaction region to collect fluorescence. The frequency stability of the laser system is measured by mixing two output laser lights which are locked by fluorescence signal and it is about 3.2 × 10~(-11) at 2048 s. The compact laser scheme is beneficial to the miniaturization and industrial production of optically pumped Cs beam clocks. The design is also appropriate and useful for other laser frequency stabilization applications.