Surface plasmon nanophotonics: A tutorial

The purpose of this tutorial is to give a practical introduction to surface plasmon nanophotonics. Surface plasmon polaritons (SPPs) are introduced as a waveguide mode at a single interface. It is shown how SPPs in nanostructures can both concentrate the local field intensity and shorten the optical wavelength. Localised surface plasmons (LSPs) are introduced and described using the quasi-static approximation. It is shown how LSPs lead to local field enhancement, which may be further cascaded to achieve additional enhancement. A brief discussion of six application areas of surface plasmon nanophotonics is given: surface plasmon resonance (SPR) sensing, SERS, enhanced fluorescence, nonlinear optics, nanolithography and sub-wavelength imaging, and optical trapping.