EXPERIMENTS ON A SEMICONDUCTOR-LASER PUMPED RUBIDIUM ATOMIC CLOCK

Experiments were carried out to improve the performances of **8**7 Rb atomic clocks by using a semiconductor laser. The experimental setup is described. Results of the measurements of the signal-to-noise ratio and linewidth of double resonance spectral line are presented to find the optimal conditions for the highest microwave frequency stability. Results of quantitative measurements on the light shift, i. e. , the microwave frequency shift induced by pumping light, are given. A novel double-resonance spectral lineshape is demonstrated, which has drastically narrower linewidth obtained by utilizing a high temporal coherence of the laser.