Plasmon resonances of gold nanoparticles incorporated inside an optical fibre matrix.

Metallic nanoparticles were incorporated into the core of standard telecommunication grade optical fibres. This creates a simple, yet robust, platform which can be used to investigate the properties of nanoparticles, for sensing, spectroscopy, and optical switching applications. The optical response of gold nanoparticles embedded in the optical fibre matrix was evaluated as a function of temperature and the use of the structure as an inline fibre-optic temperature sensor is described. A redshift in the localized surface plasmon (LSP) resonance related peak, as well as broadening of the plasmon resonance, was observed upon increasing the temperature of the nanoparticle containing fibre. The shift and broadening of the plasmon resonance were attributed to the temperature dependence of dielectric constants of metallic nanoparticles and the silica matrix and to plasmon-phonon interactions.