Electroluminescence and lasing in type II Ga Al/SbrInGaAsSb heterostructures in the spectral range 3–5 mm

We report here the study of electroluminescence and lasing in type II broken-gap Ga Al.Sb As.rInGaAsSb LPE grown heterostructures containing InGaAsSb narrow-gap active layers Egs0.27–0.3 eV.lattice-matched to GaSb substrate. Strong asymmetric band offsets of the type II heterostructures were used to provide a good electron confinement and to increase the emission efficiency. A strong dissimilarity observed in EL spectra of N-AlGaAsSbrInGaAsSbrP-AlGaAsSb laser structures was explained as due to different radiative recombination transitions. Intense room temperature spontaneous emission at ls4.2–4.6 mm with optical power output of 1.5 mW and 50 mW respectively indicates good chance for utilization in new longwavelength LED’s for ecological monitoring of gases. q1999 Elsevier Science B.V. All rights reserved.