Control of nonlinear refractive index of AuNPs doped with nematic liquid crystal under external electric field

Abstract

The nonlinear refractive index of gold nanoparticles (Au NPs) doped with nematic liquid crystal (NLC) is determined using Z-scan technique. The Au NPs were synthesized by laser ablation (Nd: YAG laser at 1064 nm) dispersed in liquid deionized water and then mixed by nematic liquid crystal. The effect of external electric field onto the nonlinear refractive index of the Au NPs was investigated using a close aperture Z-scan technique. It’s found experimentally, that the nonlinear refractive index of the Au NPs doped with E7 can be varied by changing both the compositional percentage of Au NPs and NLC molecules. The obtained nonlinear refractive index of the samples showed that E7 NLC can act as a good material for controlling the third order nonlinear coefficient due to its large nonlinear optical properties.