Plasmonics is t he study and application of surface-bound electromagnetic waves at t he interface of a metal and a dielectric called surface plasmons (SPs). Surface plasmon resonance (SPR) results from the coupling of electromagnetic radiation into electron oscillations at the metal-dielectric interface (Ozbay 2006, Stewart et al. 2008). A variety of applications have emerged that exploit the properties of SPs. e con nement of the electromagnetic wave at t he surface is a key feature in the application areas developed to date.