TY - JOUR

T1 - Antitoroidic and Toroidic Orders in All-Dielectric Metasurfaces for Optical Near-Field Manipulation

AU - Tuz, Vladimir R.

AU - Dmitriev, Victor

AU - Evlyukhin, Andrey B.

N1 - Funding information: V.R.T. acknowledges financial support from the National Key R&D Program of China Project No. 2018YFE0119900, V.D. thanks the Brazilian Agency National Council of Technological and Scientific Development (CNPq) for financial support. A.B.E. acknowledges support from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy within the Cluster of Excellence PhoenixD (EXC 2122, Project ID 390833453). The secondary multipole decomposition technique has been developed under the support of the Russian Science Foundation Grant No. 20-12-00343.

PY - 2020/11/25

Y1 - 2020/11/25

N2 - In material science, multiferroics attract significant interest due to their broad functionality originating from the ability to maintain an interaction between the magnetic and electric polarizability of matter (magnetoelectric effect). The lack of natural multiferroics usable at optical frequencies has led to the search for various approaches to synthesize nanostructures behaving as multiferroics. Herein, we propose a design and study optical properties of an all-dielectric metasurface, which resembles the multiferroic behaviors, and simultaneously maintains both toroidic and antitoroidic orders in the dynamical response on the irradiation by a linearly polarized plane wave. The metasurface is composed of trimer clusters of high-index dielectric particles (disks). The conditions of the appearance of the toroidal dipole moment in the trimer are revealed with the use of the multipole decomposition method. A special technique (secondary multipole decomposition method) is applied to find out how the multipole moments of the trimer are related to the separate multipole moments of its constitutive nanodisks. The spectral properties of the metasurface as well as the electromagnetic near-field distribution are obtained from the full-wave numerical simulation. We demonstrate that both toroidic and antitoroidic orders appear due to specific cluster symmetry reducing, where the toroidal dipole exists as a dark mode of the trimer. At the wavelengths of the toroidal dipole mode excitation, the proposed all-dielectric metasurface possesses a high-quality-factor resonant response accompanied by the near-surface confinement of the strong electromagnetic field with its concentration at the nanoscale. These features make our metasurface to be a platform for chemical or biological sensing, organic light-emitting devices, and large-area laser applications.

AB - In material science, multiferroics attract significant interest due to their broad functionality originating from the ability to maintain an interaction between the magnetic and electric polarizability of matter (magnetoelectric effect). The lack of natural multiferroics usable at optical frequencies has led to the search for various approaches to synthesize nanostructures behaving as multiferroics. Herein, we propose a design and study optical properties of an all-dielectric metasurface, which resembles the multiferroic behaviors, and simultaneously maintains both toroidic and antitoroidic orders in the dynamical response on the irradiation by a linearly polarized plane wave. The metasurface is composed of trimer clusters of high-index dielectric particles (disks). The conditions of the appearance of the toroidal dipole moment in the trimer are revealed with the use of the multipole decomposition method. A special technique (secondary multipole decomposition method) is applied to find out how the multipole moments of the trimer are related to the separate multipole moments of its constitutive nanodisks. The spectral properties of the metasurface as well as the electromagnetic near-field distribution are obtained from the full-wave numerical simulation. We demonstrate that both toroidic and antitoroidic orders appear due to specific cluster symmetry reducing, where the toroidal dipole exists as a dark mode of the trimer. At the wavelengths of the toroidal dipole mode excitation, the proposed all-dielectric metasurface possesses a high-quality-factor resonant response accompanied by the near-surface confinement of the strong electromagnetic field with its concentration at the nanoscale. These features make our metasurface to be a platform for chemical or biological sensing, organic light-emitting devices, and large-area laser applications.

KW - dark modes

KW - metamaterials

KW - Mie theory

KW - nanostructures

KW - subwavelength structures

KW - Toroidal modes

UR - http://www.scopus.com/inward/record.url?scp=85096866936&partnerID=8YFLogxK

U2 - 10.1021/acsanm.0c02421

DO - 10.1021/acsanm.0c02421

M3 - Article

AN - SCOPUS:85096866936

VL - 3

SP - 11315

EP - 11325

JO - ACS Applied Nano Materials

JF - ACS Applied Nano Materials

IS - 11

ER -