A systematic study of Surface Plasmon Enhanced Electric Field in Nanoparticle Dimers for UV Plasmonics

Abstract

Surface plasmon mediated electric field enhancement in the dimer arrangement of Al, Ag and, Au nanoparticles using multipole spectral expansion (MSE) approach has been studied. MSE method has flexibility and simplicity in extending the approach to treat an arbitrary arrangement of nanoparticles by solving corresponding general eigenvalue problem. The field enhancement behavior of Al, Ag, and Au nanoparticle dimers has been investigated, covering UV-VIS spectral range. The role of embedding medium, particle-particle separation, and the metal type were studied. The resonance wavelength showed the red shift with increasing the dielectric constant of the ingrained material. The red shift with increasing particle size and the dielectric constant of embedded or ingrained medium has been studied. This study was used to design plasmonic nanoparticle dimer with resonant optical response at crucial wavelengths in UV-VIS spectral region.