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

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 (n2=-1.63×10-7cm2/W) and nonlinear absorption coefficient (β=-1.7×10-3cm/W) at the wavelength 632.8 nm of He-Ne. The negative sign of the nonlinear refractive index n2 indicates that this material exhibits self-defocusing optical nonlinearity. These results show that Basic Green 1 dye has potential applications in nonlinear optics.