Lengthening of the photoluminescence decay time of InAs quantum dots coupled to InGaAs/GaAs quantum well

Time-resolved photoluminescence measurements are carried out for InAs quantum dots (QDs) coupled through a GaAs barrier to an In0.3Ga0.7As quantum well (QW). It is found that decay time of photoluminescence response from the QW is significantly shortened when compared to a reference sample only containing a QW with similar parameters while the decay time of photoluminescence response for the QD layer is significantly lengthened compared to reference sample only containing a QD layer. A rate equation model is developed to describe the observed behavior via carrier capture from QW to QD states in the QD:QW structure. (c) 2006 American Institute of Physics.