All-dielectric optical “huygens source”

The concept of all-dielectric nanoantennas operating in optical frequency domain is suggested. A huygens source consisting of a high-permittivity dielectric sphere excited by a point-like dipole is considered. We demonstrate that in addition to the electric resonance, the sphere exhibits a very strong magnetic resonance, resulting in a narrow radiation pattern, overall high nanoantenna directivity and radiation direction control. To verify the proposed concept experimentally we scale up the nanoantenna design to microwave frequency range. We find an excellent agreement between the experimental data and numerical results and verify directly high-performance characteristics of the all-dielectric antennas.