Optical echo phenomenon in the system of two-level atoms beyond the mean field a

摘要

Abstract: The occurrence of optical echo phenomena in two-level media is analyzed beyond the mean field approximation. The polarization of the medium and the intensity of the echo signal depend in a complex way on both the areas of the pulses and on the area of the `material' field and the relation between (on the one hand) the photon densities of each pulse and (on the other) the density of two-level atoms (excitons) of the medium.!3