Surface plasmons are electromagnetic modes that are present at the interface of a metal and dielectric material. Depending upon the structure of the metal, surface plasmons demonstrate a wide range of characteristics, such as optical field enhancements, tunable resonances, and the ability to propagate in films or be confined at nanoparticle defects. As a result, surface plasmons continue to generate growing interest for new sensor technologies, energy transport, and photonics applications. In many cases, the most interesting advantages of surface plasmons lie in the optical near-field, significantly below the diffraction limit of conventional optics in at least one dimension. This requires novel methods for imaging the spatial profile and propagation properties of surface plasmons, as well as novel spectroscopies for studying photochemistry of heterostructured materials in the near-field. In this talk, recent efforts in our group for the imaging and spectroscopy of plasmonic heterostructures are discussed, specifically applied to plasmonic continuum spectroscopy, metal nanoparticle photoluminescence, and coherent coupling of molecular excitons to surface plasmons.

ANL Physics Division Colloquium Schedule