WELL-WIDTH DEPENDENCE OF THE EXCITONIC LIFETIME IN STRAINED III-V QUANTUM-WELLS

The dependence of the excitonic lifetime on the well width in InGaAs/InP (unstrained), InGaAs/GaAs, and InGaAsP/InP strained quantum well heterostructures is investigated by time-resolved photoluminescence spectroscopy. We show that the main contribution to the lifetime variation comes from the change of the exciton binding energy. In the strained InGaAs/GaAs wells, the widest wells have a shorter lifetime than expected. We attribute this to the onset of plastic relaxation.