Yb:YAG slab laser amplifier

A laser amplifier based on an active element in the shape of a Yb:YAG slab is developed. It combines the propagation of an amplified elliptical beam without internal reflections, the use of high-brightness diode pump channel combining, and a heat sink made of silicon carbide. Its laser characteristics and factors limiting the output pulse energy are studied. It is shown that the application of an active element with gradient doping ensures stable operation of the laser head at pump powers of ∼0.5 kW. The use of signal radiation diverging along one axis compensates for the effect of reducing the output cross section of the amplified beam; as a result, a gain of G = 4 is ensured with a beam quality factor M ² < 1.4.