Time-resolved photoluminescence measurements of InAs self-assembled quantum dots grown on misorientated substrates

Time-resolved photoluminescence decay measurements have been performed on samples with varying-sized self-assembled InAs/GaAs quantum dot ensembles, formed by substrate misorientation. Ground-state radiative recombination lifetimes from 0.8 to 5.3 ns in the incident power density range of 0.05–3400 W cm−2 at a temperature of 77 K have been obtained. It was found that a reduction of the quantum dot size led to a corresponding reduction of the radiative lifetime. The evident biexponential decay was obtained for the ground state emission of the quantum dot array, with the slower second component attributed to a carrier recapturing process.