Efficient, high-power, Al-free active-region diode lasers emitting at &lgr;=0.83 &mgr;m have been grown by low-pressure metalorganic chemical vapor deposition. Threshold-current densities as low as 220 A/cm2,maximum continuous wave (cw) power of 4.6 W, and a maximum cw wallplug efficiency of 45&percent; are achieved from 1 mm long, uncoated devices withIn0.5(Ga0.5Al0.5)0.5Pcladding layers. Further improvement is obtained by replacing thep-In0.5(Ga0.5Al0.5)0.5Pcladding layer with thin (0.1 &mgr;m) electron-blocking layers ofAl0.85Ga0.15AsandIn0.5(Ga0.5Al0.5)0.5P,and ap-In0.5(Ga0.9Al0.1)0.5Pcladding layer. Such devices provide a record-highT0of 160 K and reach catastrophic optical mirror damage (COMD) at a record-high cw power of 4.7 W (both facets). The corresponding COMD power-density level (8.7 MW/cm2)is ∼2 times the COMD power-density level for uncoated, 0.81-&mgr;m-emitting AlGaAs-active devices. Therefore, 0.81-&mgr;m-emitting, Al-free active-region devices are expected to operate reliably at roughly twice the power of AlGaAs-active region devices. ©1997 American Institute of Physics.