Strong near-field couplings of anapole modes and formation of higher-order electromagnetic modes in stacked all-dielectric nanodisks  

作　　者：Bin Liu Ma-Long Hu Yi-Wen Zhang Yue You Zhao-Guo Liang Xiao-Niu Peng Zhong-Jian Yang 刘彬;胡马龙;章艺文;游悦;梁钊国;彭小牛;杨中见(Hubei Key Laboratory of Ferroelectric and Dielectric Materials and Devices,Faculty of Physics and Electronic Science,Hubei University,Wuhan 430062,China;Hunan Key Laboratory of Nanophotonics and Devices,School of Physics and Electronics,Central South University,Changsha 410083,China)

机构地区：[1]Hubei Key Laboratory of Ferroelectric and Dielectric Materials and Devices,Faculty of Physics and Electronic Science,Hubei University,Wuhan 430062,China [2]Hunan Key Laboratory of Nanophotonics and Devices,School of Physics and Electronics,Central South University,Changsha 410083,China

出　　处：《Chinese Physics B》2022年第5期666-669,共4页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant Nos.11704416 and 11704107);the Hunan Provincial Natural Science Foundation of China(Grant No.2021JJ20076);the Hubei Provincial Natural Science Foundation of China(Grant No.2020CFB557)。

摘　　要：We theoretically study the near-field couplings of two stacked all-dielectric nanodisks,where each disk has an electric anapole mode consisting of an electric dipole mode and an electric toroidal dipole(ETD)mode.Strong bonding and anti-bonding hybridizations of the ETD modes of the two disks occur.The bonding hybridized ETD can interfere with the dimer’s electric dipole mode and induce a new electric anapole mode.The anti-bonding hybridization of the ETD modes can induce a magnetic toroidal dipole(MTD)response in the disk dimer.The MTD and magnetic dipole resonances of the dimer form a magnetic anapole mode.Thus,two dips associated with the hybridized modes appear on the scattering spectrum of the dimer.Furthermore,the MTD mode is also accompanied by an electric toroidal quadrupole mode.The hybridizations of the ETD and the induced higher-order modes can be adjusted by varying the geometries of the disks.The strong anapole mode couplings and the corresponding rich higher-order mode responses in simple all-dielectric nanostructures can provide new opportunities for nanoscale optical manipulations.

关 键 词：all-dielectric nanodisks anapole electric toroidal dipole magnetic toroidal dipole 

分 类 号：O469[理学—凝聚态物理] TB383.1[理学—电子物理学]