Nonlinear optical response of liquid crystalline matrix doped with single walled carbon nanotube and graphene sheets

Abstract

In this work, the nonlinear optical characterization of single-walled carbon nanotubes (SWCN) and graphene in guest-host liquid crystal system have been investigated using z-scan technique and far-field diffraction patterns. The guest materials have been dispersed in 8CB smectic liquid crystal at different concentration and specific thermal conditions. Z-scan measurements with continuous wave (CW) He:Ne laser beam at 632.8nm have been used for determining the nonlinear refractive index (n2) of guest-host system. It was found that n2 depends substantially on the concentration of the SWCN and graphene layers doped in SLCs, and it led to a significant growth in the nonlinear refractive index. Furthermore, the results of far-field optical diffraction patterns under CW HeNe laser illumination have been verified the result of nonlinear properties of Z-scan measurements.