Enhanced optical limiting in polystyrene-ZnO nanotop composite films.

In this work we investigate the optical limiting property of polystyrene-zinc-oxide (ZnO) nanotop composite films, using an open aperture Z-scan technique. The nanocomposites are prepared for different loading concentrations of ZnO and are fabricated using spin and dip coating techniques. On exposing the films to a pulsed nanosecond laser at 532 nm, the nonlinear absorption (NLA) coefficient is found to be greater for spin-coated films compared to dip-coated films. The measured NLA coefficient is found to be enhanced with an increase in loading concentration of ZnO in the monomer for both spin- and dip-coated films.