Optimization of laser dynamics for active stabilization of DF-VECSELs dedicated to cesium CPT clocks

摘要

We report the implementation and performance of a double servo-loop for intensity and phase-difference active stabilization of a dual-frequency vertical external-cavity surface-emitting laser (DF-VECSEL) for coherent population trapping (CPT) of cesium atoms in the framework of compact atomic docks. In-phase fully correlated pumping of the two laser modes is identified as the best scheme for intensity noise reduction, and an analytical model allows optimization of the active stabilization strategy. Optical phase locking the beat-note to a local oscillator leads to a phase noise level below -103 dBc/Hz at 100 Hz from the carrier. The laser contribution to the short-term frequency stability of the clock is predicted to be compatible with a targeted Allan deviation below sigma(y) = 5 x 10(-13) over 1 s. (C) 2020 Optical Society of America