Carrier trapping effects on photoluminescence decay time in InGaN/GaN quantum wells with nanocluster structures
Journal
Journal of Applied Physics
Journal Volume
101
Journal Issue
6
Date Issued
2007
Author(s)
Abstract
Carrier dynamics in InGaN∕GaN quantum wells (QWs) with compositional fluctuations is studied with time-resolved photoluminescence (PL) experiments and Monte Carlo simulations of exciton hopping and recombination. In particular, the effects of indium-rich nanoclusters in such a QW structure on the photon-energy-dependent PL decay time are investigated. In our experiments, two InGaN∕GaN QW samples of different silicon doping conditions are used for demonstrating the two cases of different nanocluster densities. An increasing trend of PL decay time on the high-energy side of the PL spectrum is observed in the sample with high nanocluster density. Such a trend is not observed in another sample with few clusters. This difference is consistent with the simulation results which can help us in identifying the origin of the increasing trend as exciton trapping by the local potential minima in the spectral range of the free-carrier states.
SDGs
Type
journal article