InAs/GaAs quantum dot systems can emit light at the wavelengths above 1.3μm by covering the InAs quantum dots with an InxGa1-xAs strain reducing capping layer (SRCL). The presence of the SRCL relaxes the strain in the growth direction while the in-plane compressive strain remains nearly unchanged. This results in an aspect ratio increase of the quantum dot. Both the strain relaxation in the growth direction and the aspect ratio change induce a non-linear red shift. This work studies the dependence of the emission wavelength on the thickness and the indium composition of the SRCL. Experimental topologies have been simulated and a close quantitative match is found.
Quntum Dots, Electronic structure, Strain, Strain-reducing layer, Wavelength
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