Abstract
Measurements of the transition energies of GaAsSb quantum well samples with different barrier configurations reveal that the conduction band offset of the coherently strained heterojunction grown on GaAs has a zero crossing at a Sb mole fraction of . A type-I band alignment is formed for lower Sb mole fractions and a type-II band alignment is formed for higher Sb mole fractions. This occurs as a consequence of a considerable amount (58%) of the bandgap bowing being distributed to the conduction band. As a suitable active material for 1.3 μm emission, pseudomorphic grown on GaAs is determined to have a weak, , type-I conduction band offset and a bandgap energy of .
- Received 25 August 2004
DOI:https://doi.org/10.1103/PhysRevB.70.195339
©2004 American Physical Society