Plasmonics exploits the interaction between light and primarily metallic materials (in the form of thin films or nanostructures), through the excitation of localized surface plasmons (at the particle scale) or propagating plasmons (at the interface between a metal film and a dielectric).
This effect is associated with an oscillation of charge density at the surface, accompanied by a strong enhancement of the electric field in the vicinity of that surface.

Over the past twenty years, interest in plasmonics has grown significantly, notably thanks to increasingly advanced fabrication techniques such as lithography (optical, electron, etc.) and chemical synthesis. Control over topographical parameters, often at the nanometer scale, has made it possible to reveal new optical properties and further enhance them in order to meet strong technological application demands. Advances in nanotechnology at the beginning of the 21st century have enabled the coupling of plasmonic nanostructures with inorganic or organic components with various functionalities (electrical, mechanical, optical, acoustic, thermal, etc.), opening the way to a new field of study and applications known as “active plasmonics.” This concept first appeared in 2004 following experiments on manipulating the response of propagating surface plasmons using an external stimulus. Transforming a plasmonic system into an active plasmonic system therefore requires coupling a structure or metal film with an active component that allows reversible control of the response of one or both constituents.

The main research directions of the GDR are: tunable plasmonics, plasmonics for chemistry and physical transformations, and the development of active components.