  We investigated the carrier and light trapping in GaInAs/AlGaAs single
quantum well laser structures by means of time resolved photoluminescence and
Raman spectroscopy. The influence of the shape and depth of the confinement
potential and of the cavity geometry was studied by using different AlGaAs/GaAs
short-period superlattices as barriers. Our results show that grading the
optical cavity improves considerably both carrier and light trapping in the
quantum well, and that the trapping efficiency is enhanced by increasing the
graded confining potential.
