Absorption And Fluorescence In Saturation Regime Of Cs-Vapor Layer With Thickness Close To The Light Wavelength

Absorption and fluorescent spectra are obtained in saturation regime of a single beam laser spectroscopy of Cesium D-2 line, in a vapor layer with thickness close to the light wavelength. We compare experimentally and theoretically obtained spectra distinguishing between open and closed, in terms of optical pumping, hyperfine transitions. In absorption, we observe a persisting difference between open and closed transitions, in terms of Dicke narrowing, when increasing laser light intensity. In fluorescence, for open transitions we note saturation dips which do not change significantly when increasing intensity. In case of closed transition, a small feature at the fluorescence line center appears for relatively high light intensity.