Exciton Properties of Diluted CdTe/CdMnTe Quantum Wells

Optical studies of the CdTe/CdMnTe multiple quantum well structures with diluted manganese in barriers are presented. The combined measurements of photoluminescence and photoluminescence excitation allowed direct observation of the binding energies of n=l heavy- and light-hole free excitons. The quantitative approach of variation of exciton binding energies with well width and barrier potential height is given. The calculated and measured exciton binding energies are in good agreement. Photoluminescence studies also show exciton-acoustic phonon scattering dominates the broadening of the exciton line width up to T = 50 K , while T > 50 K longitudinal- optical phonon scattering contributes to the line width broadening significantly.