Resonant near-field eigenmodes of nanocylinders on flat surfaces under both homogeneous and inhomogeneous lightwave excitation

A theoretical and numerical study of the optical near field in both metallic and dielectric nanocylinders close to a dielectric surface is presented. To establish a procedure of control and analysis, we address the resonant excitation of the particle eigenmodes, either through propagating (homogeneous) or evanescent (inhomogeneous) plane-wave incidence, and compare with off-resonance cases, including the effects of multiple scattering between the particle and the flat interface. The analysis is carried out by comparing the near-field distributions with the far-field scattering efficiencies and the behavior of the corresponding Mie coefficients.