Options
A comparative study of single layer InAs SK, SML, and coupled SK-on-SML QDs heterostructure by incorporating InGaAsSb (Type-II) as capping layer
Journal
Proceedings of SPIE - The International Society for Optical Engineering
ISSN
0277786X
Date Issued
2022-01-01
Author(s)
Choudhary, Samishta
Kumar, Ravindra
Mantri, Manas Ranjan
Dutta, Anindya
Chakrabarti, Subhananda
Abstract
In this study, variation in Sb composition in In0.18Ga0.82AsYSb1-Y as capping layer (CL) over SK QDs and matrix material (MM) in 6 stacks of SML QDs for InAs SML, and strain coupled InAs SK-on-SML QDs heterostructure have been done theoretically. The structural and optical properties have been investigated through Nextnano++ software. Different single-layer SK (A-series), SML (B-series), and coupled SK-on-SML QDs (C-series) structures have been modeled for this study. Two main strain components, hydrostatic and biaxial strain have been computed simultaneously with the solution of 3-D Schrodinger's equation. The hydrostatic strain is compressive in the growth direction and gives information about carrier confinement in the conduction band while a biaxial strain is tensile in the growth direction and gives information about splitting in the valance band. There is a significant improvement of hydrostatic and biaxial strain observed for A-series and B-series structures respectively, which have quaternary capping, which helps in reduced overall strain and reduced InAs QDs desorption. In Addition to that, the coupled SK-on-SML structures (C-series) with InGaAsSb (Sb-15 and 25%) as capping layer and matrix layer possess more biaxial strain and reduced hydrostatic strain as compared to the conventional coupled structures with InGaAs as matrix material of SML and GaAs as capping layer over SK. The computed PL emission wavelength for proposed C-series structures offers a red-shift over conventional coupled structures. These configurations show type-II band alignment which can be used for various optoelectronic applications in the SWIR regime such as solar cells, long-range communication, etc. This study can be advantageous for the optimization of strain-coupled heterostructures.
Volume
11995
Subjects