Particle-in-Cell Simulation of Plasmons

Plasmons are collective oscillations of the electrons in conducting media such as metals. In many cases of interest, plasmons are typically characterized by solving the Maxwell equations, where the electromagnetic response can be described by the bulk permittivity. Motivated by the physical similarity of plasmas and oscillating conduction electrons, we present a particle-in-cell-based method of simulating plasmons. By tracking the particle position and momentum through time, which are in turn connected to the electromagnetic fields through current, we demonstrate the capability of this novel approach in elucidating information on the formation of the plasmons. Specifically, we demonstrate plasmon formation in gold nanoribbons through laser irradiation and single-electron excitation. Lastly we investigate the non-local effects of ultra-small nanoparticles approaching quantum limit.