Optical Properties of Strained Antimonide-Based Heterostructures for 1.3microns VCSELs

Photoluminescence spectra of GaAsSb.GaAs quantum wells grown by molecular beam epitaxy exhibit strong blue shifts of the emission peak with increasing excitation intensity, indicating a type II band alignment, with a small conduction band offset. The absorption spectrum is characteristic of type II quantum wells, and the gain is blue shifted with respect to the low-excitation luminescence. The type II band alignment will be an important factor for the design of 1.3microns VCSELs, in particular cavity alignment and wavefunction engineering.