>>11963759Ok, i'll try my best.
I'm going to first start with a few concepts and simplified definitions and follow up with an analogy.
There are two general categories of plasmonic waves. Localized surface plasmon resonance (LSPR) and Surface plasmon resonance (SPR). LSPR is a wave that bounces back and fourth confined in a small object (i.e. a metal nanoparticle), and SPR is a wave the propagates down the length of an object at it's surface (i.e. a thin film of metal).
So, a few conditions: First you need a conduction band, so a metal. This metal must also be confined to nanoscale dimensions e.g. a metal nanoparticle, wire, or thin film. Second, this metal must have a resonant frequency that matches an energy of incident photons that can range from near infrared all the way to the ultraviolet spectrum. Third, The metal in question cannot have any losses at this resonant frequency (e.g. photoelectric ejection, fluorescence, electronic transitions). Fourth, there are some conditions that the dielectric constants of the material must meet, but don't worry about that.
Ok so let's say we have a metal nanoparticle that meets the above conditions, e.g. a spherical gold or silver particle say ~50nm in diameter. This particle will have a resonant frequency in the visible region where the electrons in the conduction band can oscillate back and fourth. So we hit the particle with that frequency of light the electrons interact with the electric field component of the incident radiation, coupling the photons to the electrons and driving this back and fourth motion of the electrons. This causes the particle to absorb a large amount of the incident radiation and the motion of the electrons in the metal generate lots of heat (just like when you put an electric current through a metal). Some of the photons scatter back of the electrons instead of being absorbed.
