We performed low temperature photoluminescence excitation and photocur
rent measurements on tensile and compressively strained GaxIn1-xAs qua
ntum-well layers grown on GaInAsP, which was lattice matched to the In
P substrate. From these measurements the excitonic transitions in the
unstrained and strained samples can be identified. We determine the ef
fective masses in growth direction GaxIn1-xAs (0.3<x(Ga)<0.6) and the
band offsets of the GaxIn1-xAs/GaInAsP heterojunction (0.4<x(Ga)<0.6).