A computational study of the optical response of strongly coupled metal nanoparticle chains

Abstract

We study the optical responses of metal nanoparticle chains. Multiple scattering calculations are used to study the extinction cross sections of silver nanosphere chains of finite length embedded in a glass matrix. The transmission and reflection coefficients of periodic 2D arrays of silver nanospheres are also calculated to understand the interaction between nanoparticle chains. The results are in agreement with recent experiments. The splitting of plasmon-resonance modes for different polarizations of the incident light are explored. Results on the effect of disorder are also presented.

Analytical study of the plasmonic modes of a metal nanoparticle circular array

“…The actual resonant frequencies fall in the range of 0.4 Ͻ k 0 a Ͻ 0.7 for our material parameters. By inspecting the interaction of surface charges 30 on the MNPs, we know that the normal-to-plane and radial modes have similar resonant frequencies that are lower than the single sphere resonant frequency, while the tangential mode is higher. Therefore, this suggests that the linewidth of the tangential mode is much larger than that of the radial mode although their linewidths have the same form ͓␦ ϳ͑k 0 a / ͒ N+1 ͔.…”

Calculation of waveguide modes in linear chains of metallic nanorods

“…In fact, such supercell architectures correspond to experimentally realizable situations [3,4]. As discussed in [15], in the supercell approach, the optical properties of a single linear chain are already obtained when the chain-to-chain distance is about 2 times longer than the interparticle distance in each chain. Our calculations show that, for a y about 5 times larger than a x , the optical response of the arrays remains practically unaltered.…”

“…Different methods have been employed for the theoretical investigation of the optical properties of such chains, e.g., Mie scattering theory [1,12], the finite-difference time-domain method [13], the dynamic eigenmode analysis [14], the multiple-scattering method [15], and the Green's function method [16,17]. However, the most popular approach is based on the assumption that the nanoparticles can be assimilated to point dipoles interacting with each other.…”

Plasmonic nanowires arranged in Fibonacci number chain: Excitation angle-dependent optical properties

“…Until now, most of the studies on finite chain of metallic nanostructures have considered uniform size of individual entities. 19,[23][24][25][26][27][28][29] In contrast to this convention, it would be interesting to explore alternative linear geometries which could give rise to some unfamiliar optical properties that are otherwise absent in conventional chain of plasmonic nanostructures. Recently, we have shown 30,31 that certain principles of deterministic inhomogeneity in the size and arrangement of plasmonic nanostructures can be harnessed to obtain unconventional array of nanophotonic elements.…”