Resonator induced plasmon filter: theoretical study

We study theoretically the plasmon mediated propagation of light through a chain of metallic nanoparticles along which a small chain (called a resonator) is attached vertically. The effect of this vertical resonator is to induce peaks and zeros in the transmission power. We show that, with a resonator constituted of two metallic clusters, an appropriate choice of the geometrical parameters can lead to a narrow peak in the transmission spectrum. This may be realized for this device by adjusting the distances between the two resonator clusters and the chain cluster to which they are attached. This enables us to get, in particular, a sharp peak between two zeros of transmission close to each other or sharp dips between two transmission ones. Such a device can be useful as a selecting or rejecting plasmon filter.