Nanoscale color control of TiO_2 films with embedded Au nanoparticles

摘要

We demonstrate an efficient nanoscale control of the optical properties of TiO_2 films by tuning the Surface Plasmon Resonance (SPR) in the embedded Au nanoparticles. The films were grown by reactive magnetron sputtering. SPR tuning was achieved by different annealings, which affected the shape and size of the Au nanoparticles, and also the phase of the dielectric matrix. These changes promoted the variations on the optical properties. As shown by the modeling of the effective dielectric function of the TiO_2/Au in the SPR region, the variation of their optical absorption spectra correlates with morphological changes.