Coupled Plasmon Oscillations in a Cluster Consisting of Three Silver Nanocylinders with Different Diameters

Abstract

2D problem of the diffraction of the TM plane electromagnetic wave by a cluster consisting of three self-similar silver nanocylinders with different sizes is considered. Rigorous numerical procedures are used to study quasi-static plasmon resonances in such a cluster. Frequency characteristics of the scattering cross section and spatial structure of the field in the vicinity of the cylinders are calculated for different angles of incidence of the plane wave, self-similarity coefficients, and diameters of cylinders. It is shown that an increase in the distance between the cylinders is accompanied by degeneration of the resonances of scattering cross section. When real loss of silver is taken into account, electric field at the exit of the cluster cannot be amplified by a factor of greater than 10.