MgO nanoparticle effect on nonlinear refractive index of nematic liquid crystal doped with Sudan black B dye using Z-scan method

In this paper, by capitalizing on z-scan technique and using cw He–Ne laser at 632.8 nm, we investigated the impact of added MgO nanoparticles on nonlinear optical properties of 6CHBT liquid crystal which was doped with Sudan black B dye. The applied cell had homogeneous alignment. MgO nanoparticles were added to 6CHBT liquid crystal which was doped with 0.3 wt.% Sudan black B dye at three concentrations of 0.1, 0.3 and 0.6 wt.%. It was found that the added MgO nanoparticles did not significantly change the nonlinear refractive index of the compound at 0.1 and 0.6 wt.% concentrations; however, they enhanced the nonlinear refractive index of the compound at 0.3 wt.% concentration. The accumulation of nanoparticles in high concentrations causes high scattering of light which can reduce the intensity of transmitted light and, as a result, nonlinear effects.