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arXiv · 1501.07682

Broadband optical magnetism in chiral metallic nanohole arrays by shadowing vapor deposition

Chunrui Han·Wing Yim Tam
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Abstract

We show that broadband optical magnetism can be achieved through incorporating multi-scaled 3D metallic meta-elements into Z-shaped nanohole arrays. The broadband effect arises from the excitation of multiple magnetic resonances in the meta-elements at different wavelengths. Moreover, the nanohole arrays exhibit a large transmission difference for left- and right-handed circularly polarized incident light due to the chiral arrangement of the meta-elements. More importantly, we have realized experimentally the broadband behavior for the optical range in Ag nanohole arrays fabricated by using a shadowing vapor deposition method. Our study opens up new opportunities for achieving broadband artificial magnetism at visible frequencies which allows possible applications in plasmonic bio-sensors or energy concentrators.

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Chunrui Han, Wing Yim Tam. 2015-01-30. Broadband optical magnetism in chiral metallic nanohole arrays by shadowing vapor deposition. https://doi.org/10.1063/1.4972789

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