High-power multi-emitter modules with fiber Bragg grating stabilization

The paper reports on the wavelength stabilization of high-power laser diode multi-emitter modules using as the external reflectors fiber Bragg gratings that are directly inscribed into the large mode area module delivery fiber using a femtosecond laser. Experiments have been carried out in a 200 μm fiber at 976 nm, but the approach can be extended at other fiber diameters and wavelengths. The results have demonstrated an effective stabilization over a broad driving current range, with power penalties in line or slightly lower than those of more traditional architectures that make use of discrete components, such as volume Bragg gratings, but with the advantage of not requiring the alignment of additional elements.