Bulk growth, structural, vibrational,crystalline perfection, optical and dielectric properties of L-threonine doped KDP single crystals grown by Sankaranarayanan-Ramasamy (SR) method

摘要

In the present work, the authors have grown the bulk-sized single crystals of pure (Size ～rn45 × 10 × 10 mm~3) and first time L-threonine (LT)-doped (Size ～ 85 × 10 × 8 mm~3) KDP with highrnquality by Sankaranarayana-Ramasamy (SR) method in an aqueous solution at constant temperature.rnA remarkable enhancement in the growth rate was observed from 3.2 mm/day (pure) to 6 mm/day (LTrndoped), respectively. The crystal structure, lattice parameters and growth direction were confirmed byrnpowder X-ray diffraction analysis. FT-IR study confirms the presence of L-Threonine doping in KDP.rnFurther, the vibrational modes and surface morphology was studied by FT-Raman spectroscopy alongrnwith etching treatment and shows remarkable reduction of surface defects. The optical transparencyrnof SR-grown KDP crystals was found to be enhanced from 76 to 88% due to LT doping. The opticalrnband gap was calculated for both the crystals and found to be 5.68 and 5.53 eV. Crystalline perfectionrnof the grown crystals was assessed by high-resolution X-ray diffraction, dielectric and wet chemicalrnetching studies and found to be good. The obtained result shows that the grown crystals can be usedrnfor laser applications.