Shadow-free multimers as extreme-performance meta-atoms

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.

14 pages, 9 Figures

References in corpus (4)

• An electromagnetic multipole expansion beyond the long-wavelength approximation
• Theory of metasurface based perfect absorbers
• Flat Engineered Multi-Channel Reflectors
• Scattering properties of PT-symmetric objects

Cited by in corpus (3)

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