Ultracompact all-dielectric superdirective antennas
Optics
2012-11-02 v1 Classical Physics
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.
Cite
@article{arxiv.1211.0230,
title = {Ultracompact all-dielectric superdirective antennas},
author = {Alexander E. Krasnok and Dmitry S. Filonov and Pavel A. Belov and Alexey P. Slobozhanyuk and Constantin R. Simovski and Yuri S. Kivshar},
journal= {arXiv preprint arXiv:1211.0230},
year = {2012}
}