Observation of radio-frequency coherency on excitation of hyperfine structure transitions in optically oriented atoms

Radio-frequency coherency of states which corresponds to Zeeman sublevels of optically oriented cesium atoms is observed on excitation of the hyperfine structure transitions by an amplitude-modulated u.h.f. magnetic field. The coherency signals were recorded by varying the modulation frequency as well as by changing frequency of the u.h.f. field. The shape of the signals and their behaviour are found to depend on the intensity of the u.h.f. magnetic field. The phenomena are analyzed theoretically and the experimental results are compared with the theory