Determination of the Excitonic Polariton Dispersion in CuCl by Resonant Two-Photon Raman Scattering

Abstract

Starting from Hopfield's theory of the excitonic polariton, the energies and momenta of the particles involved in a two-photon Raman scattering process may be calculated self-consistently from the direction of the exciting photons, their energy, and the direction of the scattered light. Attributing to the calculated momenta the measured energies of the emitted photons, one obtains the dispersion relation of the excitonic polaritons with a high accuracy in a semiexperimental way.