Studies on low and high temperature grown NLO crystals and fabrication of electro optic modulator using Benzil crystal

Abstract

The research and development on nonlinear optical materials have progressed impressively since the invention of laser. The nonlinear optical materials are widely applied as materials for laser modulators, detectors, frequency generators, information processing and optical storage. New materials are always being under investigation as the lists of applications of crystals are increasing. In particular, largely the bulk single crystals are being used for device fabrications. The thesis deals with growth of NLO single crystals by low and high temperature solution growth techniques and unidirectional growth method of Sankaranarayanan-Ramasamy (SR) for the present investigation. The grown crystals were characterized by various techniques. The second harmonic generation (SHG) and it s efficiency were measured using Kurtz- Perry powder method. The proposed thesis is structured into seven chapters. The second chapter discusses the synthesis, growth and characterization of 1H-Benzimidazolium hydrogen L-tartrate dihydrate (BT) single crystal by solution growth technique. The third chapter presents the synthesis, growth and characterization of 2-Aminopyridinium 4-methylbenzoate dihydrate (2A4M). The fourth chapter discusses the synthesis and growth of Bis(tetraethylammonium) bis(hydrogen L-tartrate) L-tartaric acid monohydrate (TELT) by solution growth technique. The fifth chapter deals with the growth of single crystals of La4Mo7O27 by the flux growth method using H3BO3 as the flux. The six chapter deals with the growth of benzil single crystal employing the unidirectional growth method of Sankaranarayanan-Ramasamy (SR). Half wave voltage measurement was made by applying high voltage to the crystal and the results are tabulated. The half wave voltage obtained is good and low value. The intensity variation on applied voltage is plotted as well the variation is pictured from the oscilloscope and the summary and suggestions for future research work are presented in the seventh chapter. newline newline newline