Surface plasmon resonance absorption of composite films doped with metal nanoparticles

Abstract

Composite thin films formed by nanometer-sized metal particles embedded in dielectric matrices were fabricated by codepositing the metal and ceramic targets using a pulsed laser deposition technique. The optical absorption properties were measured from 350 to 800 nm, and the absorption peak due to the surface plasmon resonance of metal particles was found. The effects of different metal particles (Au, Ag, Fe, and Co) and embedding matrices (SrTiO3, Al2O3, and TiO2) on the optical absorption properties of the composite films were discussed. Strong absorption peaks can be found in composite films doped with noble metal particles, while most transition metal particles show ordinary absorption patterns. Dielectric properties of metal particles and the refractive index of embedding matrices were responsible for the observed results.