Chirality-Assisted Phase Metasurface for Circular Polarization Preservation and Independent Hologram Imaging in Microwave Region
IEEE transactions on microwave theory and techniques(2023)
Abstract
A chirality-assisted phase is introduced to innovatively impose separate phase profiles in two circular polarization (CP) preserving channels, namely, two co-polarized output components under left-handed and right-handed circularly polarized (LHCP and RHCP) illuminations. Such a scheme is physically implemented by a proposed multi-layered meta-atom that achieves chiral characteristics by inner twisting angles between adjacent functional elements. A proof-of-concept metasurface is constructed to realize separate holographic images in two polarization-preserved fields with different propagating distances, respectively. In order to achieve sufficient utilization of the two polarization-preserved components, a further approach that can suppress polarization conversion is proposed with a polyatomic unit composed of four separate chiral meta-atoms arranged in a $2\times $ 2 array. A dual-holographic metasurface is designed to impose characters “ $L$ ” and “ $R$ ” in two co-polarized fields with little energy distributed in corresponding cross-polarized fields. A prototype of the metasurface is fabricated and experimentally measured. The measurements agree well with theoretical predictions and full-wave simulations, showing in the co-polarized field a character “ $L$ ” under LHCP incidence and an “ $R$ ” under LHCP incidence. The proposed mechanism provides a theoretical foundation for further CP channel expansion and modulations and has great potential in multifunctional antenna design and wireless communications.
MoreTranslated text
Key words
Chiral response,circular polarization (CP),hologram imaging,metasurface,microwave
AI Read Science
Must-Reading Tree
Example
Generate MRT to find the research sequence of this paper
Chat Paper
Summary is being generated by the instructions you defined