Operation of an Er:YLF laser at 1.73 µm

The performance, characterization, and optimization of an Er:YLF laser operating at 1.73 μm is described. The lifetimes of the upper and lower laser level were measured which allowed the optimum Er concentration and the ultimate performance to be predicted. In addition, the pulse-forming network and the mirror transmissivity were optimized. The laser output energy in the normal mode and the
Q
-switched mode as well as the
Q
-switched pulselength were measured. In a separate, more efficient, laser arrangement, an output energy of 55 mJ was obtained with an overall efficiency of 0.0024.