Open AccessFrom non- to super-radiating manipulation of a dipolar emitter coupled to a toroidal metastructure
Author(s) -
Jie Li,
Xing-Xing Xin,
Jianda Shao,
Yinghua Wang,
Zhen Lin,
ZhengGao Dong
Publication year - 2015
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.23.029384
Subject(s) - toroid , dipole , optics , physics , common emitter , radiation , purcell effect , molecular physics , optoelectronics , spontaneous emission , laser , plasma , quantum mechanics
Toroidal dipolar response in a metallic metastructure, composed of double flat rings, is utilized to manipulate the radiation pattern of a single dipolar emitter (e.g., florescent molecule/atom or quantum dot). Strong Fano-type radiation spectrum can be obtained when these two coupling dipoles are spatially overlapped, leading to significant radiation suppression (so-called nonradiating source) attributed to the dipolar destructive interference. Moreover, this nonradiating configuration will become a directionally super-radiating nanoantenna after a radial displacement of the emitter with respect to the toroidal flat-ring geometry, which emits linearly polarized radiation with orders of power enhancement in a particular orientation. The demonstrated radiation characteristics from a toroidal-dipole-mediated dipolar emitter indicate a promising manipulation capability of the dipolar emission source by intriguing toroidal dipolar response.