Thin-film filter wavelength-stabilized, grating combined, high-brightness kW-class direct diode laser.

We report on kW-class dense wavelength beam combining of a laser diode module consisting of ten broad-area laser diode bars by using a novel multi-laser cavity approach based on a thin-film filter (TFF) as a dispersive optical element. The wavelength-stabilized output of the TFF cavity is beam combined upon a -1 order transmission grating. Hereby, a cylindrical telescope is used for linear dispersion-matching between the TFF and the combiner grating.

1.6 W of single-mode output power from a novel power-scaling scheme for monolithic nonplanar ring lasers.

A novel monolithic ring laser with high potential for power scaling, the disk nonplanar ring oscillator, is presented. We achieved power scaling by reducing the pump-light-induced aberrations. The basic idea of our approach is to attach a thin Nd:YAG disk to an undoped nonplanar YAG ring resonator while the other side of the disk is mounted on a heat sink.