Photoluminescence dynamics of cavity polaritons under resonant excitation in the picosecond range

We present a calculation of time-resolved photoluminescence of cavity polaritons including scattering by acoustic phonons. Under resonant excitation to the lower-energy polariton, the calculated initial decay time, as a function of the detuning between the exciton and the cavity mode, is found to be in excellent agreement with the experimental measurements of Sermage et al. [Phys. Rev. B. 53, 16 516 (1996)]. Moreover, this model of perfectly delocalized polaritons describes qualitatively the overall dynamics under resonant excitation of the polariton states. However, the role of inhomogeneous broadening seems to be important to describe quantitatively the photoluminescence decay at long time delays.