High output power characteristics in broad-channeled substrate inner stripe lasers

A high output power AlGaAs laser is newly developed in the spectral range of 770–780 nm. The laser has a double-depth channel on the p-GaAs substrate which forms a built-in optical waveguide having a double effective refractive index/loss step. This novel waveguide is effective to make the fundamental lateral mode extremely stable; that is, up to 60 mW when the reflectivity of the front facet (Rf) is 0.12, and 100 mW when Rf is 0.04. cw threshold currents are 35–45 mA and external differential efficiencies are 0.6–0.8 mW/mA. Also, an astigmatic distance below 3 μm is obtained when Rf is more than 0.10.