Investigação das propriedades ópticas não-lineares de cristais líquidos esméticos dopados com nanobastões de ouro

Abstract

The present work is devoted to the study of the nonlinear optical properties of smectic samples containing gold nanoparticles with a rod shape. By using the time-resolved Z-scan technique, we determine the nonlinear refractive and absorptive coefficients at the vicinity of the smectic-A-nematic phase transition. Our results reveal that such coefficients are sensitive to the sample temperature. In particular, we show that the nonlinear refractive index presents a singular behavior close to the transition temperature. Further, we show that a nonlinear optical response may take place at temperatures where the smectic order is well established. We provide a detailed discussion of the effects associated with the introduction gold nanoparticles on the mechanisms behind the optical nonlinearity in liquid-crystal samples.