Investigation on Thermal, Optical, Second Order and Third Order NLO Properties of a Nonlinear Optical Single Crystal of L-Leucinium Hydrogen Maleate (LLM)

Organic Nonlinear optical (NLO) single crystals of L–Leucinium Hydrogen Maleate (LLM) have been grown by the slow evaporation solution growth technique at room temperature. The X-Ray diffraction studies proved that the LLM crystals belong to monoclinic system with noncentrosymmetric space group (C2). The decomposition and thermal strength of the LLM crystals were established by TGA/DTA studies. UV-vis-NIR absorption study shows good transparency of the LLM crystal and the lower cut-off wavelength was found to be 212 nm. The optical band gap, reflectance, refractive index and electrical susceptibility were also calculated. Second order efficiency of the LLM crystal was determined using Kurtz and Perry powder technique. Third order nonlinear studies were performed using Z-Scan technique. Nonlinear parameters such as nonlinear refractive index, absorption coefficient, and nonlinear optical susceptibility were evaluated for the LLM crystal.