Investigation of optical nonlinearity of 8-hydroxyquinolinium 2-chloroacetate and 8-hydroxyquinolinium (Z)-3-carboxyacrylate salts by Z-scan technique

• Two novel hydroxyquinolinium salts were investigated Z-scan technique.
• The nonlinear optical parameters (β, n2 and χ3) of the samples are calculated.
• Our results show that the NLO properties are enhanced with Cl atom.

A novel two organic salts: 8-hydroxyquinolinium 2-chloroacetate and 8-hydroxyquinolinium (Z)-3-carboxyacrylate were synthesized and characterized using UV–visible, FTIR and NMR measurements. The characterization spectra confirm the expected molecular structure of the prepared salts. The Z-scan technique is used to achieve optical nonlinearity measurements with a CW Diode laser at 635 nm wavelength and 14.5 mW power. The nonlinear optical absorption coefficient (β) and nonlinear refraction (n2) of the two studied compounds were affected by Cl group more than OH. The reverse saturable absorption (RSA) mechanism was responsible for the optical limiting effect. The results suggest that this material considers as a promising candidate for future optical devices applications.