An anisotropic coding metasurface (CM) is proposed for achieving circular-to-linear polarization conversion and beam deflection. Different phase coding consequences were independently achieved for two orthogonal linear polarized (LP) waves. Thus by elaborately designing coding sequences of the metasurfaces, different functions can be achieved, respectively for waves polarized along two orthogonal directions. More importantly, for circularly polarized (CP) wave, anisotropic CM can achieve circular-to-linear polarization conversion and beam deflection simultaneously. As a proof, a 1-bit anisotropic CM with 0101…/0101… and 0000…/1111… coding sequences respectively for two orthogonal LP waves was designed. The simulation results indicated that the incident CP wave is deflected into two x-polarized waves in x-o-z plane and two y-polarized waves in y-o-z plane. Both the simulation and experimental results verify the circular-to-linear polarization conversion performance of the anisotropic coding metasurfaces. The proposed anisotropic coding metasurfaces have the potential for the applications of multifunctional devices.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6706409 | PMC |
http://dx.doi.org/10.1038/s41598-019-48812-y | DOI Listing |
ACS Nano
November 2024
ICFO-Institut de Ciencies Fotoniques, Castelldefels ,08860 Barcelona, Spain.
Controlling excitons at the nanoscale in semiconductor materials represents a formidable challenge in the quantum photonics and optoelectronics fields. Monolayers of transition metal dichalcogenides (TMDs) offer inherent 2D confinement and possess significant exciton binding energies, making them promising candidates for achieving electric-field-based confinement of excitons without dissociation. Exploiting the valley degree of freedom associated with these confined states further broadens the prospects for exciton engineering.
View Article and Find Full Text PDFThe terahertz (THz) band has a great potential for the development of communication technology, but it has not been fully utilized due to the lack of practical devices, especially actively controllable multifunctional devices. Here, we propose and demonstrate a GeSbTe (GST)-based metamaterial device, where an actively controllable function is experimentally verified by inducing the crystallization process with thermal activation. Cross-polarization conversion in the reflection mode and circular-to-linear polarization conversion in the transmission mode are obtained under crystalline and amorphous GST conditions, respectively.
View Article and Find Full Text PDFPLoS One
June 2023
Xijing University, Xi'an, People's Republic of China.
In this paper, to achieve circular-to-linear polarization conversion, a novel polarization converter based on an anisotropic metasurface is proposed. Because the polarization converter is an orthotropic anisotropic structure with a pair of mutually perpendicular symmetric axes u and v, theoretical analysis shows that the polarization converter can achieve circular-to-linear polarization conversion if its reflection phase difference Δφuv under u-polarized and v-polarized incidences is close to ±90°. Numerical simulations show that the reflection phase difference Δφuv of the polarization converter is very close to +90° in two separated frequency ranges, so the polarization converter can achieve high-efficiency and dual-band CP-to-LP polarization conversion, it can convert right-handed circular-polarized (RHCP) and left-handed circular-polarized (LHCP) waves into y-polarized and x-polarized waves respectively in the two separated frequency bands of 8.
View Article and Find Full Text PDFNanomaterials (Basel)
September 2022
Department of Applied Physics, Northwestern Polytechnical University, Xi'an 710129, China.
Electromagnetic metasurfaces with excellent electromagnetic wave regulation properties are promising for designing high-performance polarization control devices, while the application prospect of electromagnetic metasurfaces is limited because of the current development situations of the complex structure, low conversion efficiency, and narrow working bandwidth. In this work, we design a type of reflective terahertz metasurface made of a simple structure that can achieve multiple polarization modulation with high efficiency. It is shown that the presented metasurface can realize ultra-broadband, cross-polarization conversion with the relative working bandwidth reaching 94% and a conversion efficiency of over 90%.
View Article and Find Full Text PDFDifferent from conventional optical waveplates, which suffer from limited functionalities and bulky configurations, metasurfaces provide full-range birefringence control along with unprecedented capabilities of wavefront shaping at any wavelength range of interest with properly designed anisotropic meta-atoms, thereby resulting in miniaturized planar meta-waveplates with excellent and fancy functionalities beyond the conventional counterparts. In this Letter, we design a set of dielectric metasurface quarter-wave plates (QWPs) that enable efficient circular-to-linear polarization conversion along with complete phase control over the converted linearly polarized beam under circularly polarized (CP) excitation. Capitalizing on this meta-QWP platform, we numerically demonstrate two advanced multifunctional meta-QWPs (i.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!