ELASTIC-SCATTERING OF SURFACE-PLASMON POLARITONS - MODELING AND EXPERIMENT

Elastic (in-plane) scattering of surface plasmon polaritons (SPP's) is modeled by considering isotropic pointlike scatterers whose responses to the incident SPP field are phenomenologically related to their eff ective polarizabilities. Numerical simulations of single, double, and multiple scattering are presented for randomly situated scatterers sho wing the interplay between different orders of scattering and localiza tion phenomena. Correlation between the scattering regimes and spatial Fourier spectra of the corresponding SPP intensity distributions is c onsidered. Various optical microcomponents (e.g.. straight and curved micromirrors) formed by sets of point scatterers are also simulated, a nd the stability and dispersion of their characteristics are investiga ted. The appropriate experimental results for SPP scattering by both r andom and specially configured sets of microscatterers are reported fo r two excitation wavelengths (594 and 633 nm) and different metal (sil ver and gold) films. The near-field optical images obtained are relate d to the calculated SPP intensity distributions demonstrating that the model developed can be successfully used in studies of SPP elastic sc attering, e.g., to design the microcomponents for SPP's. [S0163-1829(9 8)07039-8].