Well-width dependent studies of InGaN-GaN single-quantum wells using time-resolved photoluminescence techniques

Abstract

We present a well-width-dependent study of InGaN-GaN single-quantum wells using a time-resolved photoluminescence (PL) technique. At room temperature (RT), carrier recombination was found to be dominated by interface-related nonradiative processes. The dominant radiative recombination at RT was through band-to-band free carriers. For the sample grown at a higher growth rate, we observed a longer luminescence lifetime, which was attributed to an improved quantum-well (QW) interface. At low temperatures, the carrier recombination was found to be dominated by radiative recombination through a combination of free excitons, bound excitons, and free carriers. A decrease of radiative exciton lifetime was observed with decreased QW thickness.