Effects of AlGaAs inserting layer on the optical properties of InGaAs/GaAs quantum dots

Abstract

We report effects of AlGaAs inserting layer (IL) on the optical properties of InGaAs/CaAs quantum dots. Thin AlGaAs insertion layer were positioned right after the formation of self-assembled InGaAs quantum dots on GaAs buffer layer. The low temperature (15 K) photoluminescence peak typically appears at around 1.1 mum in the sample without IL whereas it is red-shifted up to 1.25 mum according to the thickness of IL. The quantum dot emission wavelength can be controllably changed from 1.1 mum to 1.25 mum by increasing the IL thickness. It is expected that thin AlGaAs IL may play a role of release layer of strain between QDs and capping layer.