Abstract

The study of fluorescence spectra under the action of a resonant laser wave is fundamental in the understanding of the radiation interaction with matter. It is well known (see, e.g., Ref. 1) that for a two-level medium at low density the shape of such a spectrum looks like a symmetrical triplet with sidebands separated from the central component by the generalized Rabi frequency. However, in the case of a strong laser field, the two-level approximation of real atomic systems very often is not adequate since it is necessary to take into account the influence of the nearest levels. In the alkali metal vapors this implies that the Rabi frequency is of the order of the doublet-splitting value. In the present paper we report what we believe to he experimental observation of many-component resonance fluorescence spectra of a three-level atomic system in the intense laser field caused by the Rabi splitting of the ground 3S and two exited 3P states of the sodium atom on six quasi-energy levels (see Fig. 1).

© 1994 Optical Society of America