Optical Measurements of Electronic Band Structure in Tensile Strain (Ga,In)P-(Al,Ga,In)P Quantum Wells

Low-temperature (5-K) photoluminescence excitation spectroscopy has been used to identify the principal interband transition energies in a series of tensile strained (Ga,In)P single quantum wells. The structures were of nominally fixed composition but covered a range of well widths from 15 to 120. Fitting of the observed transition energies, using an envelope-function model based on bulk valence-band dispersion calculations that include the interaction with the spin-split-off band, indicates a conduction-band discontinuity ΔEc of ∼0.7ΔEg. This is close to that predicted by a modified model-solid-theory calculation.