Effect of Solvent on Third-Order Nonlinear Optical Behavior of Reactive Blue 19 Dye

The present work focuses the study of effect of solvent on third-order nonlinear optical (NLO) properties of reactive blue 19 dye dissolved in various polar solvents, namely ethanol, DMF and DMSO, respectively. Fourier Transform Infrared Spectroscopy (FT-IR) was used to find the functional groups present in reactive blue 19 dye. Third-order NLO features of reactive blue 19 dye was examined by a low power continuous wave laser of 650 nm wavelength. Reactive blue 19 dye exhibit negative nonlinear index of refraction of the power of 10^-7 cm²/W and the nonlinear coefficient of absorption of the order of 10^-3 cm/W. Both positive and negative nonlinear absorption coefficient of reactive blue 19 dye in different polar solvents is due to the characteristic behavior of saturable and reverse saturable absorption. Third-order NLO susceptibility of reactive blue 19 dye in polar solvents was determined to be the power of 10^-6 esu. The experimental results reveal that the dye sample reactive blue 19 is a potential material for nonlinear optical applications.