  Carrying digital information in traditional copper wires is becoming a major
issue in electronic circuits. Optical connections such as fiber optics offers
unprecedented transfer capacity, but the mismatch between the optical
wavelength and the transistors size drastically reduces the coupling
efficiency. By merging the abilities of photonics and electronics, surface
plasmon photonics, or 'plasmonics' exhibits strong potential. Here, we propose
an original approach to fully understand the nature of surface electrons in
plasmonic systems, by experimentally demonstrating that surface plasmons can be
modeled as a phase of surface waves. First and second order phase transitions,
associated with percolation transitions, have been experimentally observed in
the building process of surface plasmons in lattice of subwavelength apertures.
Percolation theory provides a unified framework for surface plasmons
description.
