Resonant exciton excitation photoluminescence and dynamics in a GaAs/AlAs multiple quantum well with internal electric field

The stability of excitons with large oscillator strengths at room temperature has been of great significance in device applications. In this paper, we report the effects of the ultrafast dissociation of excitons confined in a quantum well on optical characteristics. The photoluminescence spectra show components of higher energy than the excitation energy and a nonlinear increment of the intensity. Furthermore, the spectrally resolved pump–probe signals at the exciton energies elucidate the change in the exciton position. These results indicate the importance of the exciton stability in optical devices, in particular emission type, including terahertz wave, based on excitons.