Propagation of localized surface plasmons in sets of metallic   nanocylinders at the exit of subwavelength slits
  We analyze, by means of numerical simulations, transmission enhancements through sub- wavelength slits due to the presence of sets of plasmonic nanocylinders, placed near the exit of these apertures. Further, we extend this study to photonic crystals of dipolar plasmonic particles in front of an array of extraordinarily transmitting slits practiced in a metallic slab. 
F.J. Valdivia-Valero and M. Nieto-Vesperinas
physics.optics