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arXiv · 1502.02205

Invisible nanowires with interfering electric and toroidal dipoles

Wei Liu·Jianfa Zhang·Bing Lei·Haojun Hu·Andrey E. Miroshnichenko
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Abstract

By studying the scattering of normally incident planewaves by a single nanowire, we reveal the indispensable role of toroidal multipole excitation in multipole expansions of radiating sources. It is found that for both p-polarized and s-polarized incident waves, toroidal dipoles can be effectively excited within homogenous dielectric nanowires in the optical spectrum regime. We further demonstrate that the plasmonic core-shell nanowires can be rendered invisible through destructive interference of the electric and toroidal dipoles, which may inspire many nanowire based light-matter interaction studies, and incubate biological and medical applications that require non-invasive detections and measurements.

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Wei Liu, Jianfa Zhang, Bing Lei, Haojun Hu, Andrey E. Miroshnichenko. 2015-05-20. Invisible nanowires with interfering electric and toroidal dipoles. https://doi.org/10.1364/ol.40.002293%2010.1364%2Fol.40.002293

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