A VARIATIONAL CALCULATION OF LIGHT-HOLE ENVELOPE FUNCTIONS AND EXCITON BINDING-ENERGIES IN (GA, IN)AS-GAAS QUANTUM-WELLS

We have performed a self consistent calculation for both the heavy-hole and light-hole excitons in (Ga, In)As-GaAs quantum wells. The self-consistent light-hole wave function has been found to peak either in the alloy layer or in the GaAs layer, depending both on the indium content and thickness of the (Ga, In)As layer. We have calculated the average light-hole and electron positions and have found that both type I and type II excitons can be obtained from a type II band to band profile with a marginal light-hole potential in agreement with spin orientation measurements.