Resonant Raman Scattering by excitonic polaritons in semiconductors

We report results on Resonant Raman Scattering (RRS) mediated by excitonic polaritons in a high-purity semiconductor (CdTe) at low temperatures. For the first time ingoing and outgoing resonances at the n = 1, 2, 3 exciton states are detected on the one and two LO-phonon RRS. The transformation at resonance of sharp Raman peaks into well-thermalized exciton luminescence bands is observed for every ingoing, outgoing or intermediate state resonance.