Effects of the local environment on plasmonic coupling of metallic nanotube arrays

Abstract

We have theoretically investigated the effect of the dielectric core and the dielectric embedding medium separately on the transmission spectra and plasmonic properties of coupled metallic nanotube arrays. It is found that the plasmonic properties of the nanotube arrays are strongly influenced by the presence of the dielectric which induces additional screening charges. We show that instead of one single photonic bandgap for the hollow nanotube arrays placed in air, an additional photonic bandgap arises from the presence of dielectric media in the transmission spectra. Based on the localized nature of the electric field distributions, we also clearly show the presence of the local plasmonic resonant modes that originate from multipolar plasmon polaritons in the cross section of these nanotube arrays, and that a large amount of opposing surface charges are built up in the gap between adjacent nanotubes.