Evaluation of nonlinear optical parameters of TiN/PVA nanocomposite – A comparison between semi empirical relation and Z-Scan results

•We report on the third order optical non linearity of TiN/PVA nanocomposites.•Optical properties were studied from both theoretical and experimental method.•The results derived from theoretical method deviated greatly from the experimental.

We report on the third order non linearity of TiN/PVA nanocomposites. Linear and nonlinear optical properties were studied from theoretical and experimental method. Theoretical method involved Tichy and Ticha relation pooled with generalised Miller's rule. During the study dispersion of refractive index is analysed using the Wemple–Di Domenico single oscillator model. Z-Scan was used as the experimental tool. The results derived from theoretical method deviated greatly from the experimental. We believe that such incongruity is due to the SPR property of the TiN nanoparticle whose SPR peak almost coincides with the irradiated laser wavelength.