OPTICAL-PUMPING SATURATION EFFECT IN SELECTIVE REFLECTION

The reflection from a dielectric-atomic vapor interface displays reson ance behavior in the vicinity of an atomic line (selective reflection) . At normal incidence, a sub-Doppler structure arises which is due to the symmetry-breaking presence of the interface. The optical saturatio n of the selective reflection signal for the cesium D1 line is investi gated and a different saturation behavior for atoms leaving the surfac e and atoms moving toward the surface is found. The experimental resul ts agree with reasonable accuracy with the predictions derived from a three-level atomic model. The saturation effect may be important for t he correct interpretation of long-range atom-wall interaction and of c ollision-induced broadening measurements, for which selective reflecti on spectroscopy is particularly suitable.