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arXiv · 1401.8032

Broadband chiral metamaterials with large optical activity

Kirsty Hannam·David A. Powell·Ilya V. Shadrivov·Yuri S. Kivshar
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Abstract

We study theoretically and experimentally a novel type of metamaterial with hybrid elements composed of twisted pairs of cross-shaped meta-atoms and their complements. We reveal that such two-layer metasurfaces demonstrate large, dispersionless optical activity at the transmission resonance accompanied by very low ellipticity. We develop a retrieval procedure to determine the effective material parameters for this structure, which has lower-order symmetry ($\mathrm {C}_4$) than other commonly studied chiral structures. We verify our new theoretical approach by reproducing numerical and experimental scattering parameters.

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Kirsty Hannam, David A. Powell, Ilya V. Shadrivov, Yuri S. Kivshar. 2014-01-30. Broadband chiral metamaterials with large optical activity. https://doi.org/10.1103/physrevb.89.125105

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