Band offsets at heavily strained III - V interfaces

In consequence of the progress made in epitaxial techniques, strained layers are important parts of a few of today's optoelectronic devices. Much attention has thus been paid to the question of how the band line-up at a heterojunction is affected when one or both constituents are strained. This article reports experimental results on band offsets at heavily strained heterojunctions of arsenide compounds. The InAs/GaAs and InAs/AlAs heterojunction valence-band offsets are markedly strain dependent. Emphasis is placed on photoemission experiments and on the modifications of the classical core-level method due to the strain. The results are compared with theoretical data from both `model' theories and self consistent calculations.