The molecular beam epitaxy grown metamorphic heterostructures with InAs/InGaAs quantum dots emitting in the wavelength range of \( \sim \) 1.55 μm were studied using structural and optical characterization techniques. These heterostructures contain InxGa1 – xAs/GaAs(001) metamorphic buffer layers with different thickness and composition profiles. The maximum In content in the compositionally graded InxGa1 – xAs layer was \({{x}_{{\max }}} = 0.44\) with its thickness varying in the range from 220 to 1100 nm. A correlation was established between the observed features in the photoreflectance and photoluminescence spectra and parameters of the metamorphic heterostructures. It is shown that the highest-energy S-shaped feature in the photoreflectance spectra is associated with transitions in the InxGa1 – xAs inverse layer located near the structure surface. The shoulder observed in the low-temperature photoluminescence spectra on the short-wavelength side of the broad peak associated with emission from InAs/InGaAs quantum dots can be attributed to transitions from the upper part of the InxGa1 – xAs metamorphic buffer layer.
