Growth and characterization of KDP single crystals by Sankaranarayanan-Ramasamy (SR) method

Abstract

Pure KDP single crystals were studied extensively since the 1930s because they could be grown easily to reach a large size, of their low cost and piezoelectric property. Since then, many applications of the KDP crystal have been developed such as the electro-optic modulation, the optical switch (Q-Switch) and the frequency of laser converter through the second-, third-order nonlinear effects. In response to these applications, the high-quality KDP single crystals are required. The common method of growing KDP crystal is the temperature lowering, in which a KDP seed is placed in a supersaturated solution. The disadvantage of this method is the spontaneous appearance of crystalline clusters at the bottom of the container which retard the growth of the main crystal. Since the 2010s, Sankaranarayanan and Ramasamy have proposed a new method of growing crystal by designing the Y-shaped solution container. In this study, the KDP single crystals were grown by the SR method. These crystals have better quality, fewer defects, higher hardness and density, and especially material saving compared to the ones prepared by the traditional methods.