Plasmonic Fano Resonance in Metallic Disk-Like Nanostructure System

Fano resonance, theoretically explained by U. Fano, is a type of resonant scattering phenomenon in the quantum system that results from interference between discrete and continuous state energy, and gives rise to an asymmetrical line-shape. In recent years, plasmonic Fano resonance has been found in the plasmonic structure system, which is produced by the interaction between the superradiation mode and the subradiation mode supported by the structure. Because the Fano resonance has narrow frequency lincwidth, weak radiative losses, and strong near-field enhancement on the surface of structures, it has attracted much attention in the field of photonics. The disk-like structure which has the ability of supporting wider superradiation lincwidth can couple with one or more subradiation patterns supported by the structure to excite and modulate single or multiple Fano resonances effectively. Moreover, the disk-like nanostructured systems can still excite high-intensity plasmonic Fano resonance under the case of highly geometric symmetry or regularly multi-individual composition, which can further expand the design of Fano resonant nanostructures. In this paper, we summarized the disk-like Fano resonance nanostructure, including single disk structure, heterogeneous dimer disk structure and multipolymer disk structure, and presented the mechanism and excitation of the plasmonic Fano resonance. In addition, we also briefly discussed the applications of disk-like Fano resonance nanostructure.