MMP Simulation of Plasmonic Particles on Substrate Under E-Beam Illumination

A novel numerical approach to investigate the resonance behavior of plasmonic particles on a substrate under e-beam illumination is presented. The method is based on the Multiple Multipole Program (MMP), a generalized point matching technique, and is augmented by the ability to compute layered media and electron energy loss spectroscopy (EELS) measurements. Furthermore, the whole framework is complemented by a mesh-based method that automatically places the multipole expansions and matching points for arbitrary three-dimensional geometries. The performance of our technique is analyzed by a series of numerical experiments. The EELS responses of a plasmonic split-ring resonator in free space and a plasmonic disk dimer on a membrane, as well as the resonant modes, are simulated. Finally, our implementation is compared to the established discontinuous Galerkin time domain (DGTD) method with respect to its computational efficiency. We show significantly improved performance especially for the computation of EELS resonance maps.