Nontrivial nonradiating all-dielectric anapole

Abstract

Dynamic anapole is a promising element for future nonradiating devices, such as cloaked sources and sensors, quantum emitters, and especially the sources for observing dynamic Aharonov-Bohm effect. However, the anapole response can be damped by the Joule losses. In this paper we theoretically propose and experimentally demonstrate a novel type of active all-dielectric source, which is in some sense, realizes the elementary anapole of Afanasiev, and study its radiative/nonradiative regimes in the microwave range.

Anapole Mode Sustaining Silicon Metamaterials in Visible Spectral Range

“…All these properties lead to extensive research of all‐dielectric and, particularly, silicon metamaterials and their many applications. 2D metamaterials or metasurfaces stand out due to the simplicity of fabrication and exhibits desirable optical properties . Nevertheless, we should mention the ref.…”

Toroidal Dipole Mode Observation In Situ

“…Namely, poloidal currents, flowing along the meridians on the torus‐like objects, generate magnetic moments that circulate inside the torus, and altogether they create toroidal moments oscillating along the torus main axis . Apparently, the main interest on toroidal moment is underpinned by their contribution to more promising anapole mode excitations that take place due to destructive interference between electric and toroidal multipoles of the same order, leading to such effects as strong field localization inside the even point‐like sources and invisibility to external observer . The works of the last decade point out to feasibility of this effect in structures from microwaves to optics and demonstrate such effects as novel types of transparency, optical invisibility, and cloaking .…”

Blueshift and phase tunability in planar THz metamaterials: the role of losses and toroidal dipole contribution

“…Their exotic response is a promising platform for filling the THz frequency gap [1][2][3]. A separate class of metamaterials is the one with the toroidal response [4][5][6][7][8][9][10][11][12][13][14][15]. The toroidal observation is mediated by the excitation of currents flowing in inclusions of toroidal metamolecules, and resembles the poloidal currents along the meridians of gedanken torus [4,5].…”

“…The toroidal observation is mediated by the excitation of currents flowing in inclusions of toroidal metamolecules, and resembles the poloidal currents along the meridians of gedanken torus [4,5]. Meanwhile, the destructive interference between the toroidal and electric dipole moments leads to lack the far-fields, but the fields in the metamolecule origin describing by δ-function [6,7]. Such fields configuration, referred as the anapole, allows to observe the new effect of Electromagnetically Induced Transparency (EIT) [6,7], provides an extremely high Q-factor in metamaterials [8], enables a cloaking for nanoparticles [9,10], and is a platform for confirmation of the dynamic Aharonov-Bohm effect [6,7].…”

“…Meanwhile, the destructive interference between the toroidal and electric dipole moments leads to lack the far-fields, but the fields in the metamolecule origin describing by δ-function [6,7]. Such fields configuration, referred as the anapole, allows to observe the new effect of Electromagnetically Induced Transparency (EIT) [6,7], provides an extremely high Q-factor in metamaterials [8], enables a cloaking for nanoparticles [9,10], and is a platform for confirmation of the dynamic Aharonov-Bohm effect [6,7]. Recently, it was demonstrated the anapole excitation in planar metamaterials, which enabled an extremely high Q-factor in microwave [8], which gives promising opportunities for tunable metamaterials due to the strong electromagnetic fields localization within metamolecules.…”