Abstract

For the past six years, Lincoln Laboratory has been developing mid-infrared diode lasers based upon GaInAsSb/AlGaAsSb heterostructures grown on GaSb substrates by molecular beam epitaxy.^1-4 Compactness and efficiency make diode lasers very desirable in the mid infrared for optical pumping solid-state lasers and for direct sources in this spectral range, which is eyesafe and contains may strong molecular absorption lines. Band gaps and lattice constants of the III-V alloys used in this work are shown in Fig. 1. GaInAsSb alloys lattice matched to GaSb lie along the dashed line and can have band gap wavelengths ranging from 1.7 to 5 μm by adjusting the composition. As was found for GaAs and InP lasers, quantum-well active regions (particularly those under compressive strain) have led to many mid-infrared laser performance breakthroughs.^1-3 In addition, early life-tests on these devices have indicated good reliability.

© 1994 IEEE