Time-resolved photoluminescence studies of annealed 1.3-μm GaInNAsSb quantum wells
1 Institute of Physics, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, Wroclaw 50-370, Poland
2 Solid State and Photonics Laboratory, Stanford University, Stanford, CA 94305-4075, USA
Nanoscale Research Letters 2014, 9:81 doi:10.1186/1556-276X-9-81Published: 17 February 2014
Time-resolved photoluminescence (PL) was applied to study the dynamics of carrier recombination in GaInNAsSb quantum wells (QWs) emitting near 1.3 μm and annealed at various temperatures. It was observed that the annealing temperature has a strong influence on the PL decay time, and hence, it influences the optical quality of GaInNAsSb QWs. At low temperatures, the PL decay time exhibits energy dependence (i.e., the decay times change for different energies of emitted photons), which can be explained by the presence of localized states. This energy dependence of PL decay times was fitted by a phenomenological formula, and the average value of E0, which describes the energy distribution of localized states, was extracted from this fit and found to be smallest (E0 = 6 meV) for the QW annealed at 700°C. In addition, the value of PL decay time at the peak energy was compared for all samples. The longest PL decay time (600 ps) was observed for the sample annealed at 700°C. It means that based on the PL dynamics, the optimal annealing temperature for this QW is approximately 700°C.