Enhancement of carrier confinement in pseudomorphic In x Ga1- x As/GaAs strained quantum wells using interfacial AlAs layers

Pseudomorphic In _x Ga₁_ _x As/GaAs quantum well structures with one or two monolayer of interfacial AlAs inserted between the In _x Ga₁_ _x As layers and the GaAs barriers were studied. The growth parameters were determined using reflection high-energy electron diffraction(RHEED) intensity oscillations in a molecular beam epitaxy(MBE) system. The presence of two monolayer-wide interfacial AlAs was confirmed through high resolution transmission electron microscope(HRTEM). In photoluminescence(PL) spectra a large spectral blue shift of the excitonic transitions was observed.