Comparative studies of glycine added potassium dihydrogen phosphate single crystals grown by conventional and Sankaranaryanan-Ramasamy methods

Glycine added potassium dihydrogen phosphate (KDP) crystals have been grown by slow evaporation solution technique, slow cooling along with seed rotation and Sankaranaryanan-Ramasamy (SR) method. The size of the grown crystal in slow cooling method was 35 x 25 x 20 mm(3) and in SR method it was 20 mm in diameter and 110 mm in length. The grown crystals were subjected to powder X-ray diffraction, UV-Vis, thermal analysis, Vickers microhardness, dielectric, laser damage threshold, higher resolution X-ray diffraction (HRXRD) and nonlinear optical (NLO) studies. All the grown crystals have good transparency in the entire visible region. In order to determine mechanical strength of crystal, Vickers micro-hardness measurement was carried out. Dielectric study reveals higher dielectric constant and low dielectric loss for SR method grown crystal. High laser damage threshold was observed in SR method grown glycine added KDP crystal compared to SR method grown pure KDP crystal. The second harmonic efficiency of the glycine added KDP is increased compared to pure KDP. (C) 2012 Elsevier B.V. All rights reserved.