Characterization of the ultrafast resonant secondary emission from GaAs quantum well

The coherent and incoherent components of the resonant secondary emission from GaAs quantum well structures after ultrashort excitation have been studied as a function of the excitation density, lattice temperature, and inhomogeneous broadening by means of interferometric correlation techniques. We find that the coherent emission is thermally quenched and saturates with the excitation power. A good agreement is found within a simple classical model based on the inhomogeneous broadening of the excitonic band, including the experimental excitonexciton and exciton-phonon induced dephasing.