Explanation of annealing-induced blueshift of the optical transitions in GaInAsN/GaAs quantum wells

This letter aims to describe the effect of rapid thermal annealing on a Ga0.64In0.36As0.99N0.01/GaAs single quantum well grown by molecular-beam epitaxy. This effect was investigated using both photoluminescence and photoreflectance. A blueshift of optical transitions and a change of character of the ground-state transition were observed after annealing. We show that this behavior can be explained by a combination of two annealing-induced effects: A change in the nearest-neighbor configuration of nitrogen atoms and a simultaneous change in the quantum well profile due to atom diffusion across the quantum well interfaces.