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arXiv · 1602.08145

Excitation of radiationless anapole mode of isotropic dielectric nanoparticles with tightly focused radially polarized beam

Lei Wei·Zheng Xi·Nandini Bhattacharya·H. Paul Urbach
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Abstract

A high index dielectric nano-sphere can be excited and yet remain radiationless. A method to excite the non-radiating anapole mode of a high index isotropic dielectric nanosphere is presented. With tightly focused radially polarized beam illumination, the main-contributing electric dipole mode and magnetic modes can be zero with only a weak electric quadruple contributing to the total scattering. Further, with a standing wave illumination formed by two counter-propagating focused radially polarized beam under $4π$ configuration, the ideal radiationless ananpole can be excited.

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Lei Wei, Zheng Xi, Nandini Bhattacharya, H. Paul Urbach. 2016-02-25. Excitation of radiationless anapole mode of isotropic dielectric nanoparticles with tightly focused radially polarized beam. https://doi.org/10.1364/optica.3.000799

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