Characterization of high average power Nd:GGG slab lasers

Performance characteristics of zig-zag optical path Nd:GGG slab lasers are reported. The sizes of the crystals are 6/sup t/ mm*10/sup w/ mm*100/sup l/ mm and 10/sup t/ mm*18/sup w/*167/sup l/ mm. These crystal slabs were polished with surface flatness of lambda /5 ( lambda =6328 AA), surface roughness of 8 AA rms, and surface parallelism of 10 s. In normal model oscillation, average output powers of 45 W were obtained with the smaller slab and 145 W with the larger slab. In Q-switched operation, an average output power of 11 W has been obtained, with a pulse width of 10 ns and repetition rate of 20 Hz. Long operating life has been also achieved by suppressing solarization of the Nd:GGG crystal with UV-cutoff filters placed in the pumping cavity.<
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