Photon Echoes and the Structure of Wannier Excitons

Abstract

AbstractThe coherent polarization of a Wannier exciton system, induced by a short incident resonant light pulse, is calculated within a formalism that takes into account explicitly the internal structure of excitions. By examining the phase‐space filling interactions among excitons, it is shown that the hydrogenic structure of excitions causes significant deviations in their coherent optical response when compared with the response of the traditional two‐level model of optical coherence. This suggests that photon echo experiments, which measure directly the coherent polarization, may provide information on the structure of Wannier excitons.