6.1 W continuous wave front-facet power from Al-free active-region (λ=805 nm) diode lasers

Al-free active-region diode lasers grown by low-pressure, metal-organic chemical vapor deposition and emitting at λ=805 nm have been optimized for high continuous wave output power. The 1-mm-long devices consisting of an ${\mathrm{InGaAsP/In}}_{\mathrm{0.5}}{\mathrm{Ga}}_{\mathrm{0.5}}{\mathrm{P/In}}_{\mathrm{0.5}}{\mathrm{(Ga}}_{\mathrm{0.5}}{\mathrm{Al}}_{\mathrm{0.5}}{)}_{\text{0.5}}\mathrm{P}$ laser structure have a threshold-current density, $J_{\mathrm{th}},$ of 310 ${\mathrm{A/cm}}^{\mathrm{2}}$ and relatively high values for the characteristic temperatures of the threshold current, $T_0$ (135 K), and differential quantum efficiency, $T_1$ (900 K). Lasers with 10%/90% coatings and a 100-μm-wide stripe provide a maximum cw output power of 6.1 W at a heatsink temperature of 10 °C. The devices fail due to catastrophic optical mirror damage (COMD), where the internal power density, ${\mathrm{P̄}}_{\mathrm{COMD}},$ is 17.4 ${\mathrm{MW/cm}}^{\mathrm{2}};$ that is, twice that for conventionally facet-coated, 810 nm emitting, AlGaAs active-region diode lasers.