GaInSb/AlGaAsSb strained quantum well semiconductor lasers for 1.55 mu m operation

Gallium antimonide and related compounds are promising materials for fabric ating monolithic vertical cavity semiconductor lasers operating at telecomm unications wavelengths. With that aim active layers based on Ga0.96In0.04Sb /Al0.5Ga0.5As0.04Sb0.96 multiquantum wells have been evaluated by means of a separate-confinement laser diode structure grown on a GaSb substrate by m olecular beam epitaxy. Owing to optimization of the growing process, for th e well/barrier structure, laser emission at 1.4 mu m has been obtained at 8 0 K with a threshold current as low as 15 mA for a 640 mu m long and 15 mu m wide mesa stripe structure. At room temperature laser emission occurred a t 1.55 mu m with a pulsed threshold current density of 4 kA cm(-2) accordin g to the measured characteristic temperature of 50 K. In a first attempt su ch an active layer has been included in a 1.5 mu m microcavity involving an timonide Bragg mirrors.