Dual-band polarization angle independent 90° polarization rotator using chiral metamaterial

Abstract

Abstract:The polarization angle-independent, dual-band, 90°polarization rotator presented in this paper consisted of a bilayered chiral metamaterial composed of twisted capacity-loaded I-shaped electric field-coupled resonators in C4 symmetry. Simulated and measured results consistently demonstrated that the rotator exhibited extremely low loss and high polarization ratio under dual-band conditions. We also systematically investigated the dependence of the electromagnetic response of the loaded structure on the geometric parameters. The proposed simple, easily fabricated model of a chiral metamaterial may be used in further polarization rotator applications.

Angularly stable and broadband chiral metamaterial based design for asymmetric transmission of linearly polarized waves

“…In order to quantify the AT effect of the design, the AT parameter Δ has been computed from the transmission parameters as given in Equation (5). Figure 3A plots Δ for two propagation directions.…”

“…Although some natural chiral materials, such as, proteins, quartz, sugar solutions, and DNA can rotate the polarization-plane of incoming light wave (a phenomenon called optical activity) but in general, they exhibit weak effect over narrow bandwidth. 4,5 To obtain polarization conversion over wide band and small distances (thin interface), various metasurface designs have been studied and developed. Due to their extreme low-profile, microstrip chiral designs are the leading contenders in PC applications.…”

“…The chiral geometry can rotate the plane of polarization of an incident EM wave due to strong cross coupling between induced electric and magnetic fields. Although some natural chiral materials, such as, proteins, quartz, sugar solutions, and DNA can rotate the polarization‐plane of incoming light wave (a phenomenon called optical activity) but in general, they exhibit weak effect over narrow bandwidth 4,5 . To obtain polarization conversion over wide band and small distances (thin interface), various metasurface designs have been studied and developed.…”

Versatile Cross‐Polarization Conversion Chiral Metasurface for Linear and Circular Polarizations

“…In the past decade, chiral metasurfaces (CMS), which show circular dichroism, asymmetric transmission and polarization rotation in the polarization domain, [27][28][29] have attracted an enormous study interest. [30][31][32][33][34] Various types of meta-atoms (unit cells), for instance, the cross slot, [30] the via connected double-layer slot, [35] the V-shaped slot, [36] the Z-shaped resonator, [37] the T-shaped resonator, [38] the electric field-coupled resonator, [39,40] the split ring resonator [41][42][43][44] and the split-ring spiral [45] have been reported and implemented in the design of XPCs. Due to the high Q nature of CMS, such devices usually function in a limited bandwidth.…”

“…In other words, the device will not rotate the incident wave's polarization when it is parallel with the fixed output one. A class of C4 symmetrical XPCs inspired by the concepts of ACA/AFA [24,25] and CMS [39,40,46] have been proposed. The C4 rotation symmetry allows them to transform arbitrarily directed planar LP waves into their orthogonal counterpart.…”