High power, 0.81-&mgr;m-emitting, semiconductor diode lasers are used as pump sources for Nd:YAG solid-state lasers. Devices (1-mm-long) consisting of aInGaAsP/In0.5(Ga0.9Al0.1)0.5P/In0.5(Ga0.5Al0.5)0.5Plaser structure provide a threshold-current density,Jth,of290 A/cm2and a relatively high threshold-current characteristic temperature,T0(140 K). Uncoated diode lasers (1.2-mm-long) have a maximum continuous wave output power of 5 W (both facets) at 20 °C. The internal power density at catastrophic optical mirror damage (COMD),P¯COMD,is determined to be9.1 MW/cm2;that is, 1.8 times that for GaAs-active layer, Al-free, uncoated devices. Coated, InGaAsP-active devices are expected to haveP¯COMD=18 MW/cm2,more than twice theP¯COMDof AlGaAs-active, 0.81-&mgr;m-emitting devices with the same emitting aperture. Therefore, 0.81-&mgr;m-emitting, InGaAsP-active diode lasers should operate reliably at powers at least twice those of AlGaAs-based devices with the same contact-stripe geometry. ©1997 American Institute of Physics.