Analysis of Linear and Nonlinear Optical Properties of NiO Nanoparticles by Sol-Gel Method

Nanocrystalline nickel oxide (NiO) were prepared by low cost sol-gel method and analyzed using X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectra (EDX), Raman, photoluminescence (PL) and UV-Vis-NIR spectroscopic techniques. XRD spectrum confirmed the face centered cubic structure of NiO nanoparticles and it showed polycrystalline nature without any impurity. Magnetic ordered phase related modes of NiO nanoparticles was observed from Raman spectra, which also confirmed the absence of secondary phases in NiO nanoparticles. Linear and nonlinear refractive index and optical susceptibility of NiO nanoparticles were calculated and discussed using Tauc's method and Wemple and DiDomenico single oscillator model. Calculated maximum value of third ordered nonlinear optical susceptibility (chi((3))) is 2.2 x 10(-12) revealed that the NiO nanoparticles were suitable in nonlinear optical devices applications. Simulation of second harmonic efficiency, spectral band width and quasi phase matching of NiO nanocrystals are discussed using optiFDTD.