Nonlinear Refraction and Optical Limiting Behavior of Eriochrome Cyanine R Dye Chromophore Under CW He-Cd Laser Illumination

The nonlinear optical refraction and optical limiting behavior of an organic dye, Eriochrome Cyanine R in aqueous solution, were investigated under excitation with cw He-Cd laser light at 442nm. The nonlinear optical responses of the material were studied, using single-beam Z-scan technique. Refractive nonlinearity of the samples was investigated using closed aperture Z-scan technique. All the samples exhibited a negative (defocusing) nonlinearity and large nonlinear refractive index of the order of 10-8 cm2/W. The optical limiting behavior of the dye chromophore is also demonstrated