Tuning the structural and optical characteristics of heterogeneously coupled InAs Submonolayer (SML) quantum dots grown on InAs Stranski-Krastanov (SK) quantum dots

Abstract A complete investigation on the strain and structural properties of the heterogeneously coupled InAs Submonolayer (SML) on InAs Stranski-Krastanov (SK) quantum dot (QD) heterostructure has been done. This study shows the tunability of structural and optical characteristics of this coupled SML on SK QDs by varying the strain field through growth rate and barrier thickness. Both experimental and theoretical investigations were done to understand the strain distribution within the heterostructures. The low growth rate samples exhibited lesser in- and out-plane strain, which were also reflected in the transmission electron microscopy (TEM) images. This study would help the researchers to design devices (utilizing advantages of both SK and SML QDs) for high performance solar photovoltaics.