Improving the brightness of a diode end pumped slab laser by a new pumping scheme

This report deals with a Nd:YAG slab laser partially end pumped by a diode laser stack with 40 diode lasers. The pumped volume has a rectangular gain cross section. A hybrid resonator, which is stable in the plane of the small gain cross section and off axis unstable in the perpendicular direction, is used to yield highly efficient laser operation at high beam quality. We will describe different pumping schemes, thermal behavior of slabs with different height and their influence on the beam quality. A cw- output power of 3SOW was obtained with a beam propagation factor M2 ≤ 4.