Studies on the growth aspects and characterization of some amino acids based semiorganic nonlinear optical single crystals

Abstract

Single crystals provide the purest form of samples for basic research and also serve as the base components for large number of devices. It has been realized that nonlinear optical (NLO) effect in crystals could be exploited in the visible and infrared region in many ways after the discovery of lasers. The present thesis with 6 chapters discusses the details of investigations carried out on the growth and characterization of some amino acids (L-arginine, L-histidine and L-tyrosine) based semiorganic nonlinear optical single crystals grown by low temperature solution growth technique. Effect of neutral amino acids on the growth and its properties of LAP single crystals have been investigated. In order to study the improved characteristics of L- arginine phosphate (LAP), amino acids mixed LAP crystals have been grown by slow cooling method. Optical absorption studies have been carried out using UV-Vis- NIR spectrophotometer. Thermal behavior of the amino acids mixed LAP crystals has been studied by TG and DTG analyses. Nonlinear optical characteristics have been studied using Q switched Nd:YAG laser and#411;= 1064 nm). Optical transmission studies confirm that LTHB is transparent in the entire visible region and there is no absorption of light to any appreciable extent in the visible range. Mechanical strength of the LTHB crystal is found to be promising. Thermal analysis reveals that the sample is thermally stable up to 284°C. The NLO property studies confirmed that the second harmonic conversion efficiency of the crystal is found to be better than KDP. Hence, it is concluded that the optical, NLO and thermal properties confirm the suitability of LTHB crystal for photonic device applications. L-tyrosine hydrochloride single crystal has also been grown by slow evaporation technique. The structural and thermal properties of the grow crystal have been discussed. newline