Forward four-wave mixing via recoil-induced resonances in cold cesium atoms

Abstract

Recoil-induced resonances (RIR) can be detected in experiments involving light-atom interaction where atomic external degrees of freedom play an important role. In pump-probe experiments the recoil of atoms due to absorption and emission of radiation is responsible for the amplification and attenuation of the probe beam under certain circumstances, resulting in a disperse and narrow (of the order of 10 kHz) feature in the spectrum of the probe beam. Backward four-wave mixing (BFWM) signals, via recoil-induced resonances, using cold atoms as nonlinear medium were also extensively studied during the past years. In this work it will be presented a systematic study of forward four-wave mixing (FFWM) via RIR. It will be also presented a simple theoretical model that allowed us to predict the lineshapes of the observed signals and to better understand the phenomenon studied. The model is also compared with results that are already known in order to verify its validity and predict the possibility of measure the velocity distribution of the atomic cloud in a future experiment.