High-power 808 nm ridge-waveguide diode lasers with very small divergence, wavelength-stabilized by an external volume Bragg grating.

We present data on ridge-waveguide diode lasers having a vertical far-field divergence of only 11.5 degrees (FWHM) owing to an appropriate waveguide design. The lasers emitted an optical power of more than 1 W into the spatial fundamental mode from a ridge width of 5 microm. The emission wavelength was stabilized to a narrow range around 808 nm by placing a volume Bragg grating in front of the outcoupling facet.