Bulk damage and laser conditioning of KDP and DKDP crystals with Xe-F excimer light and the 3w of a Nd:Yag laser (Abstract Only)

Samples of deuterated and hydrogenated KDP were submitted to damage tests at 355 nm and 351 nm, with a Nd:Yag laser and the Xe-F line of a excimer laser. Bulk damage was observed; the statistical occurrence and the phenomenology of this type of damage was studied in various conditions. The crystals were raster-conditioned with the excimer source, which delivered a 16 ns pulselength. Laser-conditioning was performed with increasing fluences. The highest usable fluence was limited by the occurrence of surface damage on the front of the crystals. After this irradiation, a two-fold improvement of the damaging fluences was obtained when testing with the excimer beam. However, damage statistics were almost unchanged on the Nd:Yag installation, where the pulselength is about 3 ns. This result is discussed with respect to the large scale conditioning of crystals for high power lasers.