Effects of different cation and anion interdiffusion rates in disordered In0.53Ga 0.47 As/InP single quantum wells

Abstract

The effects of different cation and anion interdiffusion rates when disordering In0.53Ga0.47As/InP single quantum wells are investigated using an error function distribution to model the compositional profile after interdiffusion. The early stages of disordering result in a spatially dependent strain buildup, which can be either compressive or tensile. The effects of this strain profile and the compositional distribution give rise to interesting carrier confinement profiles after disordering. A significantly faster cation interdiffusion rate produces a red shift of the ground-state transition energy, which with prolonged interdiffusion saturates and then decreases. A significantly higher anion interdiffusion rate causes a blue shift in the ground state transition energy, and shifts the light hole ground state above the heavy hole ground state. The results from the model are compared with reported experimental results which have been interpreted in terms of different interdiffusion rates on the two sublattices.