Resonant Brillouin scattering of excitonic polaritons in multiple-quantum-well structures

We present theoretical and experimental study of resonant Brillouin scattering of excitonic polaritons in one-dimensional multiple-quantum-well structure. We obtain general analytical results for the scattering light spectra, valid for arbitrary quantum-well arrangement. Application of our theory to the specific case of short-period superlattice shows a perfect quantitative agreement with experimental results for the height, width, and position of the Brillouin scattering peaks and allows us to determine the energy, radiative, and nonradiative decay rates of quantum-well excitons. We reveal the signatures of excitonic polariton formation in the scattering spectra and show that the spectral width and height are strongly sensitive to the number of wells in the sample.