Plasmonics - Towards Subwavelength Optical Devices

Aspects of the optical properties of metallic nanostructures sustaining surface plasmon-polaritons are reviewed, focusing on differences with dielectric counterparts for the creation of functional nanoscale optical devices such as waveguides and resonators. The ability of plasmonic structures to confine light to volumes significantly smaller than the diffraction limit of light is discussed and a number of important applications are presented, with an emphasis on structures consisting of metallic nanoparticles. The important challenge of efficient excitation of surface plasmon-polaritons in a micro-optic framework is also addressed. A unified description of both plasmonic and dielectric photonic structures using quality factor and effective mode volume as figures of merit should allow for a clear choice of materials system for microand nano-optic devices.