High-power room-temperature continuous wave operation of 2.7 and 2.8 μm In(Al)GaAsSb/GaSb diode lasers

We have fabricated and characterized 2.7 and 2.8 mum wavelength In(Al)GaAsSb/GaSb two-quantum-well diode lasers. All lasers have 2 mm cavity lengths and 100 mum apertures. Continuous wave operation up to 500 mW was recorded at 16 degreesC from 2.7 mum lasers, while 160 mW was obtained from 2.8 mum lasers. Threshold current densities as low as 350 A/cm(2) were recorded from 2.7 mum lasers with external quantum efficiencies of 0.26 photon/electrons. The maximum wall-plug efficiency was 9.2% at a current of 2.4 A. A peak power of 2.5 W was recorded in pulsed-current mode operation at 20 degreesC at 2.7 mum and 2 W at 2.8 mum. Characteristic temperatures of T-0=71 K and T-1=86 K were measured from the 2.7 mum devices. T-0=59 K and T-1=72 K for the 2.8 mum lasers. The devices have differential series resistances of about 0.18 Omega with estimated thermal resistances of about 5 K/W. (C) 2003 American Institute of Physics.