Abstract

AbstractThe photoluminescence and its temperature dependences have been investigated for InAs quantum dots (QDs) embedded in asymmetric GaAs/InxGa1‐xAs/In0.15Ga0.85As/GaAs quantum wells (DWELL structures) as a function of the In content x (x=0.10‐0.25) in the capping InxGa1‐xAs layer. Photoluminescence (PL) study reveals the red shift of QD ground state peak when x increases from 0.10 to 0.15. The significant degradation of PL intensity is monitored together with a blue shift of PL peaks and PL band broadening when x = 0.20 or 0.25. The fitting procedure has been applied on the base of Varshni analysis to PL peaks. It is shown that all DWELL structures are characterized by the same Varshni parameters that are close, but not equal, to the band gap shrinks with temperature in the bulk InAs. The last fact testifies that in studied DWELL structures the process of In/Ga intermixture between QDs and a capping layer takes place partially. However this process cannot explain the difference in PL peak positions. This difference, apparently, related to the different levels of elastic strain in DWELLs that change non monotonically due to the variation of In concentrations in capping layers. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.