Capping layer modulation of composition of GaAs/In0.15Ga0.75As/InXGa1-XAs/GaAs quantum wells and InAs QD’s emission

The GaAs/In0.15Ga0.85As/InxGa1-xAs /GaAs quantum wells (QWs) with the InAs quantum dots (QDs) have been studied by means of photoluminescence and high resolution X ray diffraction (HR-XRD) methods. The QW structures are characterized by the different compositions of capping InxGa1-xAs layers with the parameter x from the range 0.10-0.25. The InxGa1-xAs composition varying is accompanied by the change non-monotonously of the PL intensity and peak positions of InAs QD emission. HR-XRD results have been used for the control the QW compositions. Numerical simulations of HR-XRD results have shown that the composition of quantum layers vary none monotonously in studied QD structures as well. The physical reasons of the mentioned optical and structural effects and their dependence on capping layer compositions have been discussed.