Three-level photon echo for quasi-degenerated Levels

Abstract

The three-level photon echo has been described in different works [1,2] by using rotating wave approximation but none of them didnt get results which show the effects of detuning frequencies on frequency of ground level of system; also the effect distance between two generated levels on signal resonance is being neglected. In this work, we studied a -type system theoretically and numerically. By considering the Dopplers effect in environment, we get different equation for polarization of echo signal and its intensity.