Now Surface Plasmon Again

Surface plasmons are formally described by Maxwell's equations and boundary conditions, and thus often viewed as a “solved” problem in condensed matter physics ; However, recent progress in them has caused renewed interest in them. This renewed attention stems from their role in plasmonics, where nanoscale structural design and quantum effects introduce new physics and applications. Currently, surface plasmons are key to advances in nanophotonics and sensing. This issue highlights current efforts to harness their functionality and explores how even well-understood excitations can drive new scientific frontiers through changing contexts of design and application.