Study on rapid growth of highly‐deuterated DKDP crystals

Abstract

Highly-deuterated potassium dihydrogen phosphate (DKDP) crystals were grown rapidly from point seeds under high supersaturation in a temperature range of 40-60 o C. The growth rate was about 1-2 order of magnitude higher than that of the traditional temperature reduction method. It was found that highly pure raw materials, overheating at high temperature, ultrafine filtration and supersaturation stability were needed to keep the solution from spontaneous nucleation at high overcooling. The effect of growth conditions on pyramid faces was different from that of prismatic faces. The tetragonal to monoclinic phase solubility transition scarcely occurred in our experiments even though the overcooling of monoclinic phase was as high as 10 o C in some cases.

Study on optical property of rapid growth KDP and DKDP crystals

“…Potassium dihydrogen phosphate (KDP) and its deuterated analog DKDP are two of the most important nonlinear materials and the only one that can be grown to very large size [1] . In the third harmonic generation (THG) of Nd:glass laser, DKDP is preferred used to substitute KDP crystal for its weak stimulated Raman scattering (SRS) effect [2][3] . However, for the traditional temperature-reduction method of DKDP crystal growth, the growth rate is merely 0.5-1 mm/day which leads to growth cycles exceeding 1-2 years.…”

Rapid growth and properties of large-aperture 98%-deuterated DKDP crystals

“…The ICF project chooses large-aperture, highly deuterated DKDP crystals as electro-optic switch materials [9] . However, the growth of large-size, 98%-deuterated DKDP crystals faces many difficulties, such as disturbance of the monoclinic DKDP crystal during the growth of the tetragonal DKDP crystal, hydrogen–deuterium exchange, and the need for expensive heavy water [8, 10] . To date, there have been very few reports on the growth of highly deuterated DKDP crystals.…”

“…[8] reported that DKDP crystals with a deuterium content of 98% and sizes of were successfully grown by point-seed technology. The tetragonal-to-monoclinic solubility transition can be avoided by the rapid-growth technique [10] . It is essential that a rapid-growth method is used for the growth of highly deuterated DKDP crystals by the point-seed technique.…”

“…However, the growth of large-size, 98%-deuterated DKDP crystals faces many difficulties, such as disturbance of the monoclinic DKDP crystal during the growth of the tetragonal DKDP Correspondence to: G. Zheng, 155 West Yangqiao Road, Fuzhou 350002, China. Email: zhengguozong@fjirsm.ac.cn crystal, hydrogen-deuterium exchange, and the need for expensive heavy water [8,10] . To date, there have been very few reports on the growth of highly deuterated DKDP crystals.…”

“…It is essential that a rapid-growth method is used for the growth of highly deuterated DKDP crystals by the point-seed technique. The growth of largesize, highly deuterated DKDP crystals is affected by many factors [10,13] , such as the need for highly pure raw materials, supersaturation stability, ultrafine filtration, the rate of hydrogen-deuterium exchange, and the disturbance of the monoclinic crystal. At present, large-scale, high-quality, highly deuterated DKDP crystals are urgently needed for 2 X. Cai et al ICF projects, and researchers are seeking to make a breakthrough.…”