BAND ALIGNMENT IN GAXIN1-XP INP HETEROSTRUCTURES

We report low temperature optical absorption measurements on GaxIn1-xP /InP (x < 0. 2) multiple quantum wells and strained-layer superlattice s. The spectra show several well-defined peaks whose positions can be fitted within an envelope-function formalism including strain effects. We deduce conduction band offsets between the larger gap ternary and smaller gap binary materials ranging from 30 to 50 meV Since these val ues are intermediate between the strain-induced shifts for the light- and heavy-hole valence bands, the electrons and heavy holes are locali zed in the InP layers (type I system), whereas the light holes have th eir quantum wells in the GaInP layers (type II system).