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Shaping the Beam of Light in Nanometer Scales: A Yagi-Uda Nanoantenna in Optical Domain

Jingjing Li·Alessandro Salandrino·Nader Engheta
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Abstract

A Yagi-Uda-like optical nanoantenna concept using resonant core-shell plasmonic particles as its "reflectors" and "directors" is studied numerically. Such particles when placed near an optical dipole source in a certain arrangement may exhibit large induced dipole moments, resulting in shaping the far-field radiation pattern, analogous to the far field of classical Yagi-Uda antennas in the microwave regime. Variation of the ratio of radii in concentric core-shell nanostructure is used to tailor the phase of the polarizabilities of the particles, and consequently the antenna's far-field pattern. The idea of a nanospectrum analyzer is also briefly proposed for molecular spectroscopy.

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Jingjing Li, Alessandro Salandrino, Nader Engheta. 2007-03-03. Shaping the Beam of Light in Nanometer Scales: A Yagi-Uda Nanoantenna in Optical Domain. https://doi.org/10.1103/physrevb.76.245403

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