▎ 摘　　要

In this research, nonlinear optical (NLO) properties of the nematic liquid crystal doped with different concentrations of the graphene nanosheets are studied. The nematic liquid crystal molecules are aligned in parallel and perpendicular to the incident light polarization and accordingly order parameters of the aligned samples are studied using the dichroism method. We show how doped graphene nanosheets increase the nonlinear birefringence and nonlinear refractive index of the graphene guest-nematic liquid crystal host. Furthermore, we use LCR meter to obtain dielectric anisotropy of the mixture at the frequency of 1 kHz with varying temperatures. Obtained experimental results demonstrate doping 1% concentration of the graphene nanosheets increases significantly NLO properties and also the dielectric response of the nematic liquid crystal by the magnitude of two orders and shifts the phase transition point by about 15 degrees.