Polarization sensitive toroidal dipole metasurface for switch and magnetic field tunability. (23rd May 2019)

• Record Type: Journal Article
• Authors: Wang, Wudeng; Qi, Jianguang
• Is Part Of: Applied physics express. Volume 12:Number 6(2019)
• Publication Date: 2019-05-23
• Subjects: Physics -- Periodicals; Technology -- Periodicals; 621.05
• DOI: 10.7567/1882-0786/ab2137
• Languages: English
• ISSNs: 1882-0778

Abstract

Abstract: We design and numerically investigate an all-dielectric metasurface, a combination of rectangular bar and two nanoring resonators, that exhibits strong toroidal response with high polarization sensitivity and large modulation depth. With coupled-resonator effects, Fano resonance with toroidal response can be switched on and off at orthogonal orientations. Moreover, directional toroidal dipole can be achieved and controlled by symmetry breaking of metasurface, which can effectively tailor the local magnetic field with high Q -factor and strong field enhancements simultaneously, while keeps strong toroidal dipole responses. We envision that strong toroidal response in proposed metasurface has potential applications in designing switching and modulators.