Large reduction of saturation carrier densities by strain in InGaAs/AlGaAs quantum wells

Compressive strain in InGaAs/Ga(Al)As quantum wells leads to a reduction in the saturation carrier density for the bandedge exciton due to a decrease in the hole density of states. An Indium concentration of 11% gives a reduction by a factor of 9 from GaAs thereby opening a new path towards viable nonlinear optical devices. The relevant issues of carrier lifetimes and strain relief are discussed