Strain-dependent optical emission in In1-xGaxAs/InP quantum wells - art. no. 153301

InGaAs/InP strained-layer modulation-doped quantum wells were studied by ph otoluminescence. The combination of the built-in strain and the quantum con finement in this system leads to a strong valence band mixing yielding dire ct and indirect band gap structures. We demonstrate that the optical emissi on line shape is strongly dependent on the valence band dispersion and it i s a good method to distinguish between direct and indirect structures. The application of an external biaxial tensile strain to the samples provides a n additional evidence of direct-to-indirect band gap transition in strained heterostructures.