Local Plasmon Resonance: What is local plasmon resonance capable of?
Answer: When energetic photons impact on matter such as metals, their absorption causes vibrations and heat (thermal agitation). In particular the electrons are jostled. At the high radio frequencies such as microwaves such heat creation is called rotational energy and at visible light, thermal agitation. At shorter wavelengths (and higher frequencies) starting at violet light (2.95eV) incoming photons produce ionizing radiation. However when metals such as silver at very small dimensions photons of low frequencies (long wavelength) collisions between such photons with a single electron in the ‘skin depth’ of a material just below the surface, a local oscillations of the electron is caused. To some extent depending on the incoming wavelength this oscillation is referred to as a Local Plasmon Resonance. After this oscillation has expired, the departing photon may either have lost some energy (red shift in most of the time) but out of some collisions gained some energy (blue shift).