Asymmetric transmission for dual-circularly and linearly polarized waves based on a chiral metasurface

Abstract

We propose a chiral metasurface (CMS) that exhibits asymmetric transmission (AT) of double circularly and linearly polarized waves at the same frequency band. In order to realize the manipulation of electromagnetic (EM) waves in the whole space, the unit cell of CMS consists of three layers of dielectric substrate and four layers of metal patches. The Z-shaped chiral micro-structure and a grating-like micro-structure are proposed and designed to achieve AT. The simulated results show that the x-polarized wave that is incident along one direction can be transmitted into the right-hand circularly polarized (RHCP) wave and the left-hand circularly polarized (LHCP) wave that is incident along the opposite direction can be reflected as the LHCP wave in the frequency band of 4.69GHz-5.84 GHz. The maximum chirality response can be reflected by AT and circular dichroism (CD) and they can reach up to 0.38 and 0.75, respectively. In addition, we also produced the sample of CMS, and the experimental results are in good agreement with the simulated results.

Multifunctional Coding Metasurface With Left and Right Circularly Polarized and Multiple Beams

“…Circular polarization has been extensively applied in wireless satellite communications, optical displays, optical remote sensors, synthetic aperture radar imaging systems, contrast enhanced polarization micro-imaging, and biomolecular detection because of the incredible characteristics of chiral wave vector, uniform polarization distribution, lower glare effect, strong anti-interference ability, and low sensitivity between the receiver and transmitter (Lin et al, 2013;Cheng et al, 2021a;Li et al, 2021a;Li et al, 2021b;Fan et al, 2021;Han et al, 2021). In general, the left or right circularly polarized electromagnetic (EM) waves are obtained by the antennas in microwave band.…”

A single‐layer dual‐polarization transmission metasurface for multi‐feeds and multi‐focus

“…Now MSs can easily control the amplitude, phase, polarization, and other characteristics of electromagnetic wave. And it has been widely used in high-gain planar lens antenna, 10 polarization control or transformation, [11][12][13] radar cross section (RCS) reduction, 14 non-diffractive and vortex beam generation, 15 and so forth. In recent years, MSs are used to realize near-field focusing, which can be divided into reflectarray and transmitarray.…”

“…13 units form the transmissive focusing MS with size 156 Â 156 mm 2 (8.32λ 0 Â 8.32λ 0 at 16 GHz). A horn antenna with 3 dB beamwidth 19.2 is used to excite the MS. As example, two transmitarray MSs are designed:(1) MS-1 working in dual-polarizations with one feed and four focusing points, (2) MS-2 with two feeds and one focusing point.…”

A miniaturized transmission/absorption integrated frequency selection surface with ultra‐wide absorption band

“…Moreover, as a type of FSS, metasurface (MS) has aroused great research interest due to easy fabrication, low cost, and powerful functionality to manipulate the electromagnetic waves. [13][14][15] For example, absorptive MS has been designed for reducing radar cross-section (RCS). 16 By combining absorptive MS and metal ground plane, traditional FSS radomes could reflect the out-of-band incident waves to other direction and reduce the monostatic RCS.…”