Band discontinuity in strained In(As,P)/InP heterostructures

Photocurrent and photoluminescence measurements have been performed on strained InAsxP1−x/InP multiquantum wells grown by chemical beam epitaxy, for arsenic content 0.25<x<0.65 and various well widths. The energies deduced from photocurrent spectra of well-resolved electron–heavy-hole and electron–light-hole fundamental excitonic transitions are compared with calculations within the envelope function formalism including strain effects. A conduction-band offset ratio QC of 0.70±0.02 is determined and is found to be independent of the arsenic composition in wells.