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arXiv · 1609.05804

Controlling the toroidal excitations in metamaterials for high-Q response

Yuancheng Fan·Fuli Zhang·Quanhong Fu·Zeyong Wei·Hongqiang Li
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Abstract

The excitation of toroidal multipoles in metamaterials was investigated for high-Q response at a subwavelength scale. In this study, we explored the optimization of toroidal excitations in a planar metamaterial comprised of asymmetric split ring resonators (ASRRs). It was found that the scattering power of toroidal dipole can be remarkably strengthened by adjusting the characteristic parameter of ASRRs: asymmetric factor. Interestingly, the improvement in toroidal excitation accompanies increment on the Q-factor of the toroidal metamaterial; it is shown that both the scattering power of toroidal dipole and the Q-factor were increased more than one order by changing the asymmetric factor of ASRRs. The optimization in excitation of toroidal multipole provide opportunity to further increase the Q-factor of metamaterial and boost light-matter interactions at the subwavelength scale for potential applications in low-power nonlinear processing, and sensitive photonic applications.

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Yuancheng Fan, Fuli Zhang, Quanhong Fu, Zeyong Wei, Hongqiang Li. 2016-09-19. Controlling the toroidal excitations in metamaterials for high-Q response. https://arxiv.org/abs/1609.05804

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