Investigation of nonlinear optical properties of organic dye by Z-scan technique using He–Ne laser

Abstract

The third-order nonlinear optical properties of Basic Green 1 dye were measured by the Z-scan technique and measurements were carried out at different concentrations and several incident intensities. The results showed that the Basic Green 1 dye exhibited large nonlinear refractive coefficient ( n 2 = - 1.63 × 1 0 - 7 cm 2 / W ) and nonlinear absorption coefficient ( β = - 1.7 × 1 0 - 3 cm / W ) at the wavelength 632.8 nm of He–Ne. The negative sign of the nonlinear refractive index n 2 indicates that this material exhibits self-defocusing optical nonlinearity. These results show that Basic Green 1 dye has potential applications in nonlinear optics.