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arXiv · 2308.09513

Anisotropic Virtual Gain and Large Tuning of Particles' Scattering by Complex-Frequency Excitations

Grigorios P. Zouros·Iridanos Loulas·Evangelos Almpanis·Alex Krasnok·Kosmas L. Tsakmakidis
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Abstract

Active tuning of the scattering of particles and metasurfaces is a highly sought-after property for a host of electromagnetic and photonic applications, but it normally requires challenging-to-control tunable (reconfigurable) or active (gain) media. Here, we introduce the concepts of anisotropic virtual gain and oblique Kerker effect, where a completely lossy anisotropic medium behaves exactly as its anisotropic gain counterpart upon excitation by a synthetic complex-frequency wave. The strategy allows one to largely tune the magnitude and angle of a particle's scattering simply by changing the shape (envelope) of the incoming radiation, rather than by an involved medium-tuning mechanism. The so-attained anisotropic virtual gain enables directional super-scattering at an oblique direction with fine-management of the scattering angle. Our study, opening a unique light-management method, is based on analytical techniques that allow multipolar decomposition of the scattered field, and is found, throughout, to be in excellent agreement with full-wave simulations.

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Grigorios P. Zouros, Iridanos Loulas, Evangelos Almpanis, Alex Krasnok, Kosmas L. Tsakmakidis. 2023-08-18. Anisotropic Virtual Gain and Large Tuning of Particles' Scattering by Complex-Frequency Excitations. https://arxiv.org/abs/2308.09513

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