8-W CONTINUOUS-WAVE FRONT-FACET POWER FROM BROAD-WAVE-GUIDE AL-FREE 980 NM DIODE-LASERS

Al-free 980 nm InGaAs/InGaAsP/lnGaP laser structures grown by low-pres sure metalorganic chemical vapor deposition (LP-MOCVD) have been optim ized for high cw output power by incorporating a broad waveguide desig n. Increasing the optical-confinement layer total thickness from 0.2 t o 1.0 mu m decreases the internal loss fivefold to 1.0-1.5 cm(-1), and doubles the transverse spot size to 0.5 mu m (full width half-maximum ). Consequently, 4-mm long, 100-mu m-aperture devices emit up to 8.1 W front-facet cw power. cw power conversion efficiencies as high as 59% are obtained from 0.5-mm long devices. Catastrophic-optical-mirror-da mage (COMD) power-density levels reach 15.0-15.5 MW/cm(2), and are fou nd similar to those for InGaAs/AlGaAs facet-coated diode lasers. (C) 1 996 American Institute of Physics.