Control of type-I and type-II band alignments in AlInAs/AlGaAs self-assembled quantum dots by changing AlGaAs compositions

Type-I and type-II band alignments were successfully controlled by changing composition and growth temperature in AlInAs/AlGaAs self-assembled quantum dots. The Al composition dependence of the photoluminescence peak shift clearly indicated the crossover from type-I to type-II band line up and a long decay time of View the MathML source was obtained by time-resolved photoluminescence at View the MathML source for the sample with type-II band alignment grown under optimized conditions. A much longer decay component of View the MathML source was also observed from the same structure, but it may be due to slow relaxation of carriers trapped in AlGaAs matrix.