Effect of TiO2/Au nanocomposite on the optical properties of PVA film

Effects of TiO2/Au nanocomposite doped in PVA film on the structural and optical properties of polymeric film are studied experimentally. Samples are PVA films of 0.05 mm thickness, doped with different concentrations of TiO2/Au nanocomposite. Structural properties are studied from FTIR spectrum. Using the reflectance and transmittance spectrum of samples, their optical parameters includes absorption coefficient, optical bandgap energy, and refractive index are extracted. Nonlinear optical properties of doped polymer films are studied experimentally employing open and close Z-scan techniques. Experiments are performed using the second harmonic of a continuous Nd: YAG laser beam. Results show that by doping nanocomposites in PVA, the bandgap energy of samples is decreased. Real and imaginary parts of the third-order nonlinear optical susceptibility are decreased with increasing the concentration of TiO2/Au nanocomposite in the films.