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arXiv · 1211.0230

Ultracompact all-dielectric superdirective antennas

Alexander E. Krasnok·Dmitry S. Filonov·Pavel A. Belov·Alexey P. Slobozhanyuk·Constantin R. Simovski·Yuri S. Kivshar
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Abstract

We demonstrate a simple way to achieve superdirectivity of electrically small antennas based on a spherical dielectric particle with a notch. We predict this effect theoretically for nanoantennas excited by a point-like emitter located in the notch, and then confirm it experimentally at microwaves for a ceramic sphere excited by a small wire dipole. We explain the effect of superdirectivity by the resonant excitation of high-order multipole modes of electric and magnetic fields which are usually negligible for small perfect spherical particles.

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Alexander E. Krasnok, Dmitry S. Filonov, Pavel A. Belov, Alexey P. Slobozhanyuk, Constantin R. Simovski, Yuri S. Kivshar. 2012-11-01. Ultracompact all-dielectric superdirective antennas. https://arxiv.org/abs/1211.0230

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