Linear and nonlinear optical properties of innovative synthesis of nickel nanoparticles in polystyrene matrix as a new optical system

Abstract

The manuscript reports the effect of incorporation of Ni nanoparticles into polystyrene matrix on the linear and nonlinear optical properties (NLO). The Ni-PS nanocomposite films were synthesized by casting method. The structure of synthesized Ni nanoparticles was analyzed by High-resolution transmission electron microscope (HRTEM). It obvious the formation of nickel nanoparticles like needle shaped particles. The optical properties of the Ni-PS nanocomposite films have been studied from the optical reflection data recorded by UV–Visible spectrometer at typical frequencies of light in the wavelengths range of 850–2000 nm. The linear optical parameters (linear refractive index n, indirect optical energy gap (Eg), oscillator energy (Eo), dispersion energy (Ed), real and imaginary part of dielectric constants and the optical conductivity were evaluated and discussed. The indirect optical energy gap decreased from 4.54 to 3.91 eV as Ni nanoparticles increased. The dispersion of refractive index was studied using single oscillator Wemple-Di Domenico model. The third order nonlinear optical properties (χ(3)), nonlinear refractive index (n2) were found to increase as Ni nanoparticles increased and were estimated to be in the range of 7.5 × 10−19 - 9.4 × 10−14esu and 27 × 10−18 - 206 × 10−14esu respectively. The nonlinear absorption coefficient βc also increased as the Ni content increased. Furthermore, the electrical susceptibility χe and relative permittivity ɛr increased by Ni content. So, Ni-PS nanocomposite films are promising candidate for nonlinear optical devices.