Room-Temperature Operation of 2.4 μm InGaAsSb/AlGaAsSb Quantum-Well Laser Diodes with Low-Threshold Current Density

GaSb-based 2.4 μm InGaAsSb/AlGaAsSb type-I quantum-well laser diode is fabricated. The laser is designed consisting of three In_0.35Ga_0.65As_0.1Sb_0.9/Al_0.35Ga_0.65As_0.02Sb_0.98 quantum wells with 1% compressive strain located in the central part of an undoped Al_0.35Ga_0.65As_0.02Sb_0.98 waveguide layer. The output power of the laser with a 50-μm-wide 1-mm-long cavity is 28 mW, and the threshold current density is 400 A/cm² under continuous wave operation mode at room temperature.