OPTICAL AND DIELECTRIC STUDIES ON SEMIORGANIC NONLINEAR OPTICAL CRYSTAL BY SOLUTION GROWTH TECHNIQUE

The field of nonlinear optics became practically a reality after the invention of laser. High performance electro-optic switching elements for telecommunication and optical information processing are based on materials with high nonlinear optical (NLO) properties. Single crystals of nonlinear optical material Llysine sulphate (LLS) are grown by slow evaporation technique. The crystal structure and lattice parameters are determined for the grown crystal by single X-ray diffraction studies. The wide transparency range of the crystals in the visible region of the electromagnetic spectrum is identified by the UV-Vis-NIR technique. The mechanical property of the grown crystal is determined by Vicker’s microhardness test. It is observed from the microhardness studies of the grown crystals that the hardness increases with increase in load. Meyer’s index n is calculated which proves that the material belongs to soft material category. The dielectric constant and dielectric loss are calculated by varying the frequencies at room temperature. The emission of green light on passing the Nd: YAG laser confirms the second harmonic generation (SHG) property of the crystals .The SHG efficiency of the crystals are found to be better than that of Potassium Di hydrogen Phosphate (KDP)