Toroidal dipole-induced coherent forward scattering from a miniaturized cloaking structure
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The physical existence of microwave toroidal dipole in a dogbone metallic inclusion-based miniaturized cloaking structure is verified in this paper. The excitation of toroidal dipole moments on the studied composite is verified using multipole scattering formalism. The presence of the toroidal Fano resonance significantly enhances resonant forward scattering from the structure for normal incidence. Multipolar contribution from the electric, magnetic and toroidal moments significantly enhances the scattering cross-section of the composite as compared to a bare cylindrical metallic object. Applicability of the proposed scheme is tested inside an anechoic chamber using reflection measurements on the fabricated structure and is subsequently validated in computer simulations in the microwave frequency regime.
KeywordsDogbone metamaterial Forward scattering Toroidal dipole
The authors acknowledge the research funding received from the Science and Engineering Research Board (SERB), Department of Science and Technology for the major research project ECR/2017/002204.
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