Optical transmission enhancement of stacked plasmonic apertures

In this study, we demonstrate enhanced transmission for out-of-plane stacked plasmonic apertures through the interaction of localized surface plasmons of apertures using both numerical and theoretical approaches. A dispersive finite-difference time-domain (D-FDTD) model is used to investigate the systems through the numerical simulations. To explain the results of the FDTD numerical simulations and to bring further insight to this interaction, we use a magnetic coupled dipole approximation as the theoretical basis. Our results demonstrate that near-field in-phase and out-of-phase interactions of the stacked nanoholes increase or decrease the optical transmission. Plasmon hybridization is discussed for stacked nanohole dimers on out-of-plane metallic films.