Effects of Dielectric Substrate on Polarization Conversion Using Coupled Metasurfaces With and Without Tunneling

Abstract

Dielectric substrates are technologically necessary components of various microwave and optical structures and devices, and may strongly affect their performance. For metasurfaces composed of subwavelength resonators, placing dielectric components in the proximity of resonators can lead to strong modification of subwavelength resonances and related transmission regimes. We focus on the effects exerted by material and geometrical parameters of such a dielectric substrate on linear-to-linear polarization conversion that appears in quasiplanar structures containing two coupled metasurfaces and enabling chirality. It is shown that spectral locations of the polarization conversion resonances and transmission efficiency at these resonances are strongly sensitive to the substrate parameters, whereas the ability of polarization conversion and related asymmetry of transmission can be preserved in wide ranges of parameter variation. The effects of a substrate are considered in detail for the mechanisms with and without tunneling, indicating a route to compact designs of quasiplanar structures for singleand multiband polarization conversion.

Reconfigurable absorptive and polarization conversion metasurface consistent for wide angles of incidence

“…The trade-off between absorption and polarization conversion is analyzed and the final parameters are selected accordingly. The changes in the thickness of the substrate and the width of the inner resonator leads to a modification in the value of the capacitance, thus, causing changes in the surface impedance of the designed structure and, consequently, affecting the functionality of the design 5 . It is observed that by increasing the width of the inner ring resonator and the thickness of the substrate the PCR increases, while the AR decreases as depicted in Figs.…”