The application of the broad-waveguide concept to InGaAsP/InP diode la
sers has resulted in a fourfold reduction in internal loss to 1.3cm(-1
) while achieving a record low threshold current of 73A/cm(2) per quan
tum well. Output powers of 5.2W continuous wave and 10W quasi-continuo
us wave are demonstrated for 200 mu m-aperture lasers emitting at 1.43
mu m.