A Caesium Beam Atomic Clock with Laser Optical Pumping, as a Potential Frequency Standard

A passive microwave caesium beam resonator using optical pumping and optical detection, with a C.W. tunable GaAs diode laser, has been realized. The "0-0 clock transition" is detected through a change in the intensity of the fluorescence of the caesium beam. Experimental recordings of the Ramsey pattern agree with a Maxwellian distribution of atomic velocities. Results of preliminary tests, to an accuracy of a few parts in 10 11 , show good potentialities for a frequency standard of higher accuracy.