Optical resonances in a strong modulated laser beam

Abstract

The fluorescent intensity of two-level atoms irradiated by a near-resonant amplitude-modulated light wave is calculated in the Bloch model. The analogy with magnetic resonance in a strong oscillating field making an arbitrary angle with the static field is pointed out. Experimental evidence of the predicted parametric and multiple quantum resonances has been obtained with an atomic beam of sodium. Optical pumping was used to prepare the sodium atoms as two-level systems.