Reconfigurable Transmissive Meta-Gratings Using Cylindrical Plasma Discharges

In this study, we propose an innovative single-layer reconfigurable diffraction meta-gratings based on plasma technology. The meta-grating consists of a set of cylindrical plasma discharges, modelled through a free-electron permittivity with variable plasma frequency, enclosed within a high-refractive-index dielectric shell. Our findings show that, by adjusting the plasma frequencies of the discharges, it is possible to steer the direction of the main transmission lobe mode from-56° to 56°. This result is obtained through an advanced scattering engineering enabled by the combination of the negative permittivity response of plasma with high-refractive-index shell. This tunability not only enables substantial directional control in transmission mode but also ensures low reflection, achieving improved power efficiency through the structure.