Point defects and amplification in active layers of InGaAs/AlGaAs heterostructures

The energy levels of gallium and arsenic vacancies as well as silicon impurities in the band gap of In$_x$Ga$_{1-x}$As have been found as functions of the indium content. The effect of defects on the lasing output power and on the optimal reflection coefficient of output mirrors of laser diode arrays (LDAs) based on the In$_{0.11}$Ga$_{0.89}$As/AlGaAs heterostructures has been estimated. It has been shown that the lasing output power of LDAs whose active level contains defects with deep energy levels in the band gap is substantially lower (with other conditions being the same) than that of LDAs with shallow level defects in their active layers.