Nonlinear optical properties and optical power limiting behavior of Leishman dye in solution and solid polymer film using z-scan

Abstract

We have studied the nonlinear optical properties of Leishman dye in chloroform solution at different concentrations and solid film mixed with polymethylmethacrylate (PMMA) polymer using a continuous wave (CW) laser at 532nm as the excitation source. We have employed the z-scan technique to evaluate the sign and magnitude of the intensity dependent nonlinear refractive index (n2), the nonlinear absorption coefficient (β), and the third-order nonlinear optical susceptibility (χ(3)). The obtained results showed that the Leishman dye exhibits a negative nonlinear refraction (self-defocusing) and saturable absorption. It was found that the values of n2, β, and χ(3) are dependent on the dye concentration, they increases when the dye concentration increases. Optical power limiting characteristics of the dye at different concentrations in solution and solid film were also studied. Our results showed that the Leishman dye has large third-order optical nonlinearity, thus it could be a potential candidate for opto-electronic and photonic devices.