Long wavelength photoluminescence emission from InAs quantum dots embedded in GaAs matrix

Abstract

Light emission with a wavelength of 1272 nm at room temperature (RT) from self-assembled InAs quantum dots embedded in the GaAs matrix has been obtrained. Growth interruption during the formation of InAs quantum dots (QDs) on a GaAs (100) substrate has been investigated in detail. 1.9 mono layers (MLs) of an InAs QD nucleation layer was grown continuously to form a "seed" with high density. Further, the supply of up to 3 MLs of InAs with a growth interruption of 15 s for every 0.11 ML showed that photoluminescence intensity was improved by 23 times and redshifted the photoluminescence emission nearly 42 nm. The continuous growth up to 1.9 MLs helped to double the dot density. 3.3 MLs of InAs embedded in a GaAs matrix, grown using interruption showed a strong RT photoluminescence peak at around 1272 nm with a very narrow FWHM of 27.1 meV.