RYDBERG ATOMS AND RADIATION IN A RESONANT CAVITY II. EXPERIMENTS
Claude Fabre, S. Haroche, J. M. Raimond +3 more
We present various experiments involving Rydberg atoms interacting with resonant microwave electromagnetic fields inside a cavity, allowing to check different features of the theory presented in the previous paper. We first describe experiments about superradiant emission by Rydberg states in the cavity, also called transient Rydberg atoms maser ; the evolution of the system is detected either on the populations by selective field ionization technique or on the microwave field itself by heterodyne detection. Very low thresholds, down to 100 atoms, for the maser emission have been observed. We then describe various aspects of collective absorption of radiation by very excited atoms including the observation of Rabi nutation in a small applied resonant field, the study of the quantum efficiency of this set-up considered as a microwave photon counter, and finally the unexpected characteristics of the blackbody radiation absorption in the cavity.
Le Journal de Physique Colloques•Nov 1, 1982•1 citation