11W broad area 976 nm DFB lasers with 58% power conversion efficiency

A report is presented on how distributed feedback (DFB) lasers can achieve high optical power and power conversion efficiency together with a narrow vertical emission angle. Recently developed 976 nm DFB lasers emit 11 W, have a maximum power conversion efficiency of 58%, a spectral linewidth of ∼0.4  nm FWHM and a narrow vertical far field of 28° FWHM. This considerable enhancement was obtained with an improved epitaxy design and optimised grating fabrication process. These are DFB lasers that achieve power, efficiency and emission angle values comparable to conventional Fabry-Perot lasers, but with spectral stabilisation. Accordingly, these lasers are particularly well suited for pumping fibre and solid-state lasers.