Nucleation, growth, dielectric, polarizability, and Z-scan analysis of nicotinium tartrate & L-tartaric acid nicotinamide single crystals for third order NLO application: A comparative study

Abstract

ABSTRACT Organic nonlinear optical (NLO) single crystalline materials of nicotinium tartrate (NT) and L-tartaric acid nicotinamide (LTN) were grown by slow evaporation solution technique (SEST), slow cooling technique (SCT), and seed rotation technique (SRT) using water as solvent. The growth of NT and LTN crystals by SCT and SRT are reported for the first time. Formation of nucleation from the supersaturated solutions of NT and LTN were observed experimentally using an optical microscope for different duration until the formation of nucleation with well-defined morphology for the first time. The dielectric constant and loss of the grown crystals were studied as a function of temperature by varying the frequency and vice versa and the results are discussed in detail. In addition, electronic properties such as plasma energy, Fermi energy, and electronic polarizability were calculated using Penn gap and Clausius-Mossotti relation and found that the polarizability values obtained are high in the present work. The low values of dielectric constant observed at high frequency regions indicate the suitability of these materials for nonlinear and electro-optical applications. The third order nonlinear optical parameters such as nonlinear refractive index (n2), nonlinear absorption coefficient (β), and third order susceptibility (χ3) were calculated using open aperture and closed aperture Z-scan techniques using He-Ne laser for the first time.