Harnessing superdirectivity in dielectric spherical multilayer antennas

  title={Harnessing superdirectivity in dielectric spherical multilayer antennas},
  author={Roman Gaponenko and Alexander Moroz and Ilia L. Rasskazov and Konstantin Ladutenko and Alexey A Shcherbakov and Pavel A. Belov},
  journal={Physical Review B},
Small form-factor, narrowband, and highly directive antennas are of critical importance in a variety of applications spanning wireless communications, remote sensing, Raman spectroscopy, and single photon emission enhancement. Surprisingly, we show that the classical directivity limit can be appreciably surpassed for electrically small multilayer spherical antennas excited by a point electric dipole even if limiting ourselves to purely dielectric materials. Experimentally feasible designs of… 

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