Plasmon-plasmon interaction between gold nanoshells and gold surfaces

Summary form only given. Gold nanoshells are colloidal particles with a dielectric core covered by a gold shell. The plasmon resonance of the nanoshells can be tuned by varying the ratio of the core/shell radii. An enhancement in the electromagnetic energy can be found, at resonance, in the region close to the nanoshell known as the near field. It has been shown theoretically and experimentally that if the evanescent near fields of a surface plasmon polariton and a particle plasmon overlap, an efficient exchange of energy from the freely propagating electromagnetic waves into surface plasmons can be achieved. Previous experiments used particles that lacked the extraordinary tunability of nanoshells. We give our sample geometry. After evaporating a layer of gold onto a glass slide, we deposit self-assembled monolayers (SAMs) of a polymer (PDDA) and Hectorite (a synthetic clay), to control the spacing between the gold surface and the nanoshells.