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arXiv · 1212.5651

Optical toroidal dipolar response by an asymmetric double-bar metamaterial

Zheng-Gao Dong·J. Zhu·Junsuk Rho·Jia-Qi Li·Changgui Lu·Xiaobo Yin·X. Zhang
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Abstract

We demonstrate that the toroidal dipolar response can be realized in the optical regime by designing a feasible nanostructured metamaterial, comprising asymmetric double-bar magnetic resonators assembled into a toroid-like configuration. It is confirmed numerically that an optical toroidal dipolar moment dominates over other moments. This response is characterized by a strong confinement of an E-field component at the toroid center, oriented perpendicular to the H-vortex plane. The resonance-enhanced optical toroidal response can provide an experimental avenue for various interesting optical phenomena associated with the elusive toroidal moment.

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Zheng-Gao Dong, J. Zhu, Junsuk Rho, Jia-Qi Li, Changgui Lu, Xiaobo Yin, X. Zhang. 2012-12-22. Optical toroidal dipolar response by an asymmetric double-bar metamaterial. https://doi.org/10.1063/1.4757613

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