GeAlAs LASER DIODE PUMPED CESIUM BEAM FREQUENCY STANDARD

A laser diode pumped cesium beam frequency standard had been built. The laser diode used for both optical pumping and detection is frequency-locked at the 4-4 transition of Cs D₂ line. The Voltage controlled crystal oscillator(VCCO) frequency is locked to the center of the Ramsey pattern of the microwave clock transition after frequency multiplying and synthesizing. The preliminary measurement of the frequency stabilities shows that the results are in agreement with the theory, and better results could be achieved by further improving the frequency stability of the laser diode.