Third-Order Nonlinear Optical Properties of Nano NiO Thin Film Determined Using Continuous Wave Low-Power Laser

Nickel oxide nanoparticles (NiO) were produced using the sol-gel dip-coating method to create NiO/glass and silicon thin film. Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, and scanning electron microscopy were used to examine the film’s structural and optical properties. The nonlinear optical characteristics of the nickel oxide thin film were examined using the open aperture and close aperture Z-scan methods at wavelengths of 532 and 635 nm. Manipulating the laser optical intensities and wavelengths altered the refractive index of the samples in that increasing the laser intensities and wavelengths led to a decrease in the nonlinear refractive index. The nonlinear absorption coefficient exhibited a negative correlation with laser intensity and a small decreasing relationship with the wavelength.