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arXiv · 1710.09015

Shadow-free multimers as extreme-performance meta-atoms

M. Safari·M. Albooyeh·C. R. Simovski·S. A. Tretyakov
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Abstract

We generalize the concept of parity-time symmetric structures with the goal to create meta-atoms exhibiting extraordinary abilities to overcome the presumed limitations in the scattering of overall lossless particles, such as non-zero forward scattering and the equality of scattering and extinction powers for all lossless particles. Although the forward scattering amplitude and the extinction cross section of our proposed meta-atoms vanish, they scatter incident energy into other directions, with controllable directionality. These meta-atoms possess extreme electromagnetic properties not achievable for passive scatterers. As an example, we study meta-atoms consisting of two or three small dipole scatters. We consider possible microwave realizations in the form of short dipole antennas loaded by lumped elements. The proposed meta-atom empowers extraordinary response of a shadow-free scatterer and theoretically enables most unusual material properties when used as a building block of an artificial medium.

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M. Safari, M. Albooyeh, C. R. Simovski, S. A. Tretyakov. 2017-11-17. Shadow-free multimers as extreme-performance meta-atoms. https://doi.org/10.1103/physrevb.97.085412

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