OPTICAL AND DIELECTR ICSTUDIES ON SEMIORGANIC NONLINEAR OPTICAL CRYSTAL BYSOLUTION 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 i nformation processing are based on materials with high nonlinear optical (NLO) properties.Single crystals of nonlinear optical material L lysine 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 spectrumis identified by the UV-Vis-NIR technique. The mechanical property of the grown crystalis determined by Vicker’s microhardness test. It is observed from the microhardness studies of the grown crystalsthat 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 lossare 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)