Optical Limiting Methods by Z-Scan Technique for Non-Linear Optical Absorption of PVC/TiO2 Nanocomposite

To further our grasp of photonics technology, our work focuses on thin-film PVC/TiO2 nanocomposites. Nanocomposites composites were created by combining TiO2 nanoparticles with Polyvinyl Chloride (PVC) as the polymer matrix. The thin film was fabricated using the casting method. Spectral analysis was used to determine the absorbance parameters and compute the linear absorption coefficient. The nonlinear refractive index and nonlinear absorption coefficient were measured using a single beam Z-scan approach with a CW diode pumped solid state (DPSS) laser (Coherent Verdi-V5, 532 nm) acting as the excitation laser at 50mW. Peak absorption was measured at 280 nm, and as the percentage of TiO2 nanoparticles grew, more absorption was seen. The nonlinear absorption coefficient was determined to be 1x10−5 cm/W at (0.5342, 1.3585, 1.5999, and 0.0253). The poor structure arising from all of the sample morphologies affects the materials' NLO absorption. Nonetheless, they seem like good options for optical limiting applications given the positive value of NLO absorption.