Optical properties of Au-nanoparticle dispersed TiO₂ thin films prepared by laser ablation

Abstract

Au-nanoparticle dispersed TiO₂ (Au: TiO₂) films were prepared by laser ablation (pulsed laser deposition) using Au-powder mixed TiO₂ sintered targets. Au concentration in the film was controlled by target composition. A mean diameter of Au particles was increased up to 4.0 nm after heat treatment. Optical absorption spectra due to surface plasmon resonance were observed at a wavelength around 630 nm. The crystallization of Au particles and TiO₂ matrix caused the enhancement of absorption coefficient and shift of absorption peak wavelength, respectively.