Effect of Laser Radiation on the Linear and Nonlinear Optical Characteristics of Polyvinyl Alcohol/Carboxymethyl Cellulose/Nickel Oxide Nanocomposite Films

Abstract

A nanocomposite (NC) of polyvinyl alcohol (PVA), carboxymethyl cellulose (CMC), and nickel oxide (NiO) nanoparticles (NP) was prepared using sol–gel and ex-situ casting techniques. The results indicated that the NiO had a single phase with the space group (R-3m). Its average grain size was 18 nm. We used an infrared pulsed laser to irradiate the PVA/CMC/NiO NC samples with energy fluences ranging from 4 to 16 Joule/cm2. The induced changes in the linear and nonlinear optical properties of the NC samples due to the laser irradiation were investigated by means of UV spectroscopy. When the laser fluence increased up to 16 Joule/cm2, the maximum fluence used, both the direct and indirect bandgaps decreased. Additionally, we used the optical dielectric loss (ε″) to detect the type of microelectronic transition for the PVA/CMC/NiO NC samples, which was found to be a direct allowed transition. The laser effects on the absorbance, extinction coefficient, refractive index, dielectric parameters, optical conductivity, and the nonlinear parameters of the NC were studied. The enhancement in the optical properties indicated that the laser radiation is a useful tool that allows the application of the resulting PVA/CMC/NiO NC in optoelectronic devices.