Optical studies of strained type II GaAs0.7Sb0.3/GaAs multiple quantum wells

We report a detailed investigation on the optical transitions of strained type II GaAs0.7Sb0.3/GaAs (100) multiple quantum wells. For the theoretical calculations, both of the elastic deformational potential of intrinsic compressive biaxial strain, and quantum confinement effects are included. The asymmetric photoluminescence spectra reveal the features of excited state transition and quantum confinement Stark effect at high and low temperatures, respectively. The asymmetry features have also been investigated and confirmed by low-temperature photoluminescence experiments under different excitation power. From polarized photoluminescence excitation and photoconductivity spectra, both of the type I and type II optical transitions can also be clearly identified.