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We have carried out a detailed structural and optical characterization of Ga0.47In0.53As/InP multiple quantum wells grown by chemical beam epitaxy using a well-defined sequence of growth interruption times between successive layers. These growth interruption times result in the formation of interfacial layers which drastically alter the structural properties of Ga0.47In0.53As/InP multiple quantum wells. An analysis of double-crystal x-ray diffraction data reveals that exposure of InP to arsine for 2 s is sufficient to create approximately 3 monolayers of InAs0.55P0.45 ternary under biaxial compressive strain at the InP/Ga047In0.53As interface. Moreover, exposure of Ga0.47In0.53As to phosphine for 2 s results in the formation of approximately 2 monolayers of Ga0.48In0.52As0.21P0.79 quaternary under biaxial tensile strain at the Ga0.47In0.53As/InP interface. We find that long exposures to hydrides (over 5 s) rather than short ones give rise to interfacial layers with less compositional disorder and/or thickness fluctuation. Moreover, photoluminescence and absorption spectroscopy data reveal the negligible effect of InAsxP1−x and GaxIn1−xAsyP1−y interfacial layers on the emission and optical absorption properties of Ga0.47In0.53As/InP multiple quantum wells with sufficiently thick Ga0.47In0.53As layers.

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Low temperature photoluminescence measurements of GaxIn1−xAsyP1−y alloys nearly lattice matched to InP to study the line broadening of the observed band to band and near band gap transitions in these materials were performed. We find that the dominant broadening mechanism is alloy broadening that originates from the spatial fluctuations of the band gap energy due to random anion and cation distribution. A model that assumes that occupation of the group-III sites by Ga and In atoms and of the group-V sites by As and P atoms occurs randomly, is fitted to the photoluminescence spectra of our samples. This provides an excellent description of the experimental results.