High-efficiency high-beam-quality 38-W Nd:YAG slab laser end-pumped by a stack with three diode bars

A Nd:YAG slab is partially end-pumped by a diode laser stack with three diode laser bars. The pumped volume has a rectangular cross section. A hybrid resonator which is stable in the plane of small dimension and off-axis unstable in the plane of large dimension of the gain cross section was used, in order to obtain highly efficient laser operation at diffraction limited beam quality. In this paper, the laser design and experimental results are reported. 31.2 W output power was obtained with M2 equals 1.3 in the unstable plane and M2 equals 1.7 in the stable plane. 38.6 W output power was obtained with M2 equals 1.7 in the unstable plane and M2 equals 3.9 in the stable plane.