High-power and low-loss room temperature operation of 2.4μm GaInAsSb/AlGaAsSb type-I strained quantum-well laser diodes

High power GaSb based type-I GaInAsSb/AlGaAsSb three quantum wells laser diodes emitting at 2.4 μm were optimized and fabricated. The laser wafer was grown with solid source Molecular Beam Epitaxy System. With optimizations of the epitaxial structure design and the ohmic contact, the operation voltage and the internal loss decreased; the internal quantum efficiency and output power increased. The internal quantum efficiency was determined about 80.1% and the internal loss was 12 cm-1 by measuring laser diodes with different cavity lengths. An uncoated 2-mm-long laser diode with 90-μm-wide aperture exhibited a threshold current density of 222 A/cm2 (74 A/cm2 per quantum well), a continuous wave output power of 232 mW and a quasi-continuous wave (1 kHz, 10 μs) output power of 1 W at room temperature.