Beam Properties of AlGaAs Power Lasers with High-Quality Etched Mirrors

High-quality etched mirrors for AlGaAs/GaAs power lasers for applications in optical storage have been fabricated by chemically assisted ion-beam etching. In order to ensure flat mirror facets of the ridge-waveguide lasers, a flared-waveguide end section is employed. This results in a very slight mirror roughness of ~20 nm across the beam cross section, and yields excellent beam properties allowing diffraction-limited focusing up to 50 mW output power. © 1991 IEEE