Microwave Ramsey Resonances from a Laser Diode Optically Pumped Cesium Beam Resonator

Optical pumping with laser diodes is expected to improve the performance of cesium beam atomic clocks. We describe the principle of operation of the optically pumped Cs beam machine and then present Ramsey patterns obtained when one, two, or three lasers are used for the experiment. The best configuration uses two lasers, one for the state preparation yielding a complete configuration inversion, and another for efficient fluorescence optical detection, this last tuned to a recycling transition. Finally, the signal to noise (S/N) ratio is derived for this resonator and suggestions are given for its improvenment.