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arXiv · 2509.22172

Tunable Transmissive Metagratings Using Single Layer Cylindrical Plasma Discharges

Mohammad G. H. Alijani·Alessio Monti·Stefano Vellucci·Mirko Barbuto·Alessandro Toscano·Filiberto Bilotti
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Abstract

In this paper, we propose a novel single-layer reconfigurable transmissive metagrating based on plasma discharges. Each unit-cell consists of two side-by-side core-shell cylinders, with a tunable plasma core and a high-index dielectric shell. The structure is modeled using a free-electron plasma permittivity with adjustable plasma frequency. Analytical and numerical results show that the main transmission lobe can be switched between -41{\deg}, 0{\deg} and 41{\deg} by tuning the plasma frequencies. Transmission efficiency remains above 80% at broadside and 90% in the steered direction. This tunability enables effective directional control with low reflection and high overall power efficiency.

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Mohammad G. H. Alijani, Alessio Monti, Stefano Vellucci, Mirko Barbuto, Alessandro Toscano, Filiberto Bilotti. 2025-09-26. Tunable Transmissive Metagratings Using Single Layer Cylindrical Plasma Discharges. https://doi.org/10.1109/lawp.2025.3592822

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