Theoretical Treatment of the Hyper-Raman Scattering of Light Under Two-Photon Excitation Near the Lowest Exciton Level in a CdS Crystal

We theoretically study the resonant hyper-Raman scattering of light by LO-phonons in a CdS crystal with the wurtzite structure, taking into account the influence of the complex valence band on the lowest exciton state by the use of the of the perturbation theory. The scattering processes including the two-photon transitions to s- and p-excitons of the A series are considered. We show that the assumption of the possible dipole transitions between the sub-bands leads to additional scattering mechanisms, which can in some cases have a noticeable effect on the frequency dependence of the cross section.