Optical interactions in plasmonic nanostructures

Abstract

We present a review of plasmonic nanostructures in which the constituent materials are coupled together by optical interactions. The review first provides a comprehensive coverage of theoretical framework where the optical interactions are described by the multiple scattering among the nanostructures. We then discuss the two limiting cases of weak and strong interactions. The weak interaction regime is described well by the effective medium theory while the strong interaction regime requires theoretical tools that can describe the new eigenmodes delocalized over the entire system. Weakly interacting plasmonic nanostructures have been studied extensively in the metamaterials research, which has been a major research thrust in photonics during the past decade. This review covers some of the latest examples exhibiting perfect absorption and invisibility. Strongly coupled systems started to receive attention recently. As a representative example, plasmonic molecules exhibiting Fano resonance are discussed in detail. Plasmonic nanostructures offer an excellent platform to engineer nanoscale optical fields. With the recent progress in nanofabrication technologies, plasmonic nanostructures offer a highly promising pathway to discovering new phenomena and developing novel optical devices.

A Novel Metal Nanoparticles-Graphene Nanodisks-Quantum Dots Hybrid-System-Based Spaser

“…To model the optical response of nanoparticles arrays, it is fairly convenient to employ the effective medium approximation (EMA) that is only valid when the inner structure length scale is much smaller than the incident wavelength. Within EMA, the system comprising of interacting nanoparticles (NPs) is replaced by a homogeneous layer with an effective dielectric constant representing the overall response of the modeled system [38]. The effective dielectric constant for nanodisks and nanospheres arrays has been derived analytically by Genov et al through considering the RLC model of NPs arrays, in which the negative permittivity of plasmonic material and positive permittivity of dielectric are represented by inductance R-L and capacitance C respectively [39].…”

Plasmon Modes and Substrate-Induced Fano Dip in Gold Nano-Octahedra

“…One of the key properties of the plasmonic nanostructures is that their resonance frequency is highly dependent on the chemical composition, geometry, and surrounding dielectric environment, which enables broad tunability of plasmon resonance for various applications at different spectral range [5][6][7][8]. Complex plasmonic nanostructures such as oligomers, three dimensional elements, which can introduce additional tunability capability of the optical properties via strong coupling, have attracted much interest in plasmonics these years [9][10][11][12][13].…”

Describing Meta-Atoms Using the Exact Higher-Order Polarizability Tensors

“…5). This is because multipoles are efficient in describing long-range interactions but not in describing strong coupling between plasmonic particles in nearfield [61], which requires an increasingly large number of multipole order for accurate description [23]. Still, the collective responses between plasmonic particles situated in a reasonably far distance and dielectric particles [22] can be efficiently and accurately described under the multipole approach.…”