Influence of defects on the photoluminescence kinetics in GaN/AlN quantum-dot structures

The influence of defects in the AlN barrier on photoluminescence decay after pulse excitation is studied for structures with GaN quantum dots in an AlN matrix. For these quantum-dot structures, it is found that the initial part of the decay curves corresponds to fast photoluminescence decay. Comparison of the photoluminescence-decay curves for the GaN/AlN quantum-dot structures and AlN layers without quantum dots shows that fast decay is defined by the contribution of the photoluminescence band related to defects in the AlN matrix.