Effect of water impurity in CsLiB_6O_10 crystals on bulk laser-induced damage threshold and transmittance in the ultraviolet region

Abstract

We investigate the effect of water impurity in a CsLiB(6)O(10) (CLBO) crystal on the ultraviolet properties of the bulk laser-induced damage threshold (LIDT) and transmittance. The water impurity was eliminated by heating the CLBO sample with dimensions of 5 mm x 5 mm x 10 mm at 150 degrees C in an ambient atmosphere and subsequently in a dry atmosphere. The bulk LIDT of the sample after heat treatment improved by about 1.6-fold compared with that before heat treatment.

Yb Fiber Amplifier at 972.5 nm with Frequency Quadrupling to 243.1 nm

“…CLBO is also known to be hygroscopic and some performance change has been reported as the crystal absorbs or desorbs water [35]. For this reason, the CLBO crystal was operated at a temperature of 130 • C. Over a few days at this elevated temperature, the conversion efficiency increased slightly above that shown in Fig.…”

Crystal growth of CsLiB<inf>6</inf>O<inf>10</inf> in dry atmosphere

“…The pulse duration was about 8 ns. The experimental setup for the LIDTs measurement has been described in detail in our previous works [6]. The values of the LIDTs of CLBO crystals were normalized against that of fused quartz.…”

“…CsLiB 6 O 10 (CLBO) is one of the superior nonlinear optical crystals to generate deep ultraviolet (DUV) light. We have grown high-quality CLBO crystals by using solution-stirring top-seeded solution growth (SS-TSSG) method from self-flux solutions prepared by a mixing-in-aqueous-solution technique [1,2].…”

Crystal growth of in a dry atmosphere and from a stoichiometric melt composition

“…However, further reduction of the water impurity by the post-growth heat treatment would appear to be difficult, based on the results of our previous paper [6]. Thus, we suppose that the best means to decrease the degree of water impurity is to grow CLBO crystals containing low levels of water.…”

“…CsLiB 6 O 10 (CLBO) is a nonlinear optical (NLO) crystal and of interest as the wavelength-conversion crystal used in all-solidstate ultraviolet (UV) lasers [1]. NLO crystals used for conversion of high-power UV light tend to be damaged by UV light.…”