Plasmonic anapole states of active metamolecules

authored by
Gui Ming Pan, Fang Zhou Shu, Le Wang, Liping Shi, Andrey B. Evlyukhin
Abstract

Anapole states, accompanied by strong suppression of light scattering, have attracted extensive attention in recent years due to their supreme performance in enhancing both linear and nonlinear optical effects. Although both low- and high-order anapole states are observed in the dielectric particles with high refractive index, so far few studies have touched on the topic of plasmonic anapole states. Here we demonstrate theoretically and numerically that the ideal plasmonic anapole states (strong suppression of electric dipole scattering) can be achieved in metallic metamolecules via increasing the coupling strength between Cartesian electric dipole and toroidal dipole moments of the system. The increasing coupling is based on compensation of ohmic losses in a plasmon system by introducing of a gain material, the influence of which is well described by the extended coupled oscillator model. Due to suppression of dipole radiation losses, the excitation of anapole states in plasmonic systems can result in enhancement of the near fields in subwavelength spatial regions outside of nanoparticles. That is especially important for developments of nonlinear nanophotonic and plasmonic devices and active functional metamaterials, which provide facilities for strong light energy concentration at the nanoscale. Development of the considered anapole effect with increase of metamolecule components is discussed.

Organisation(s)
Institute of Quantum Optics
PhoenixD: Photonics, Optics, and Engineering - Innovation Across Disciplines
External Organisation(s)
China Jiliang University
Westlake University
Type
Article
Journal
Photonics research
Volume
9
Pages
822-828
No. of pages
7
ISSN
2327-9125
Publication date
29.04.2021
Publication status
Published
Peer reviewed
Yes
ASJC Scopus subject areas
Electronic, Optical and Magnetic Materials, Atomic and Molecular Physics, and Optics
Electronic version(s)
https://doi.org/10.1364/PRJ.416256 (Access: Closed)