Multi-functional Metasurface: Visibly and RF Transparent, NIR Control and Low Thermal Emissivity

TL;DR

This paper introduces a multi-functional metasurface that is transparent in visible and RF spectra, offers high NIR control, low thermal emissivity, and enhances 5G communication and energy conservation through innovative dielectric-metal coatings.

Contribution

It presents a novel, tunable, and scalable metasurface design with high optical and RF transparency, outperforming traditional low-emissive glass materials for energy-efficient and communication-enhanced applications.

Findings

92% RF transmission at 30 GHz

86% optical transparency at 550 nm

<0.2 thermal emissivity

Abstract

Rapid advances in metamaterial technology are enabling the engineering of wave-matter interactions heretofore not realized and functionalities with potentially far-reaching implications for major challenges in the fields of energy conservation and radio frequency (RF) communication. We propose a visibly and RF transparent composite metasurface utilizing dielectric-metal spectrally selective coatings with high NIR control and low thermal emissivity, thus achieving a multi-functional metasurface capable of enhancing 5G communication efficiency and exhibiting energy conservation features. The proposed meta-glass yields 92% peak RF transmission at 30 GHz which corresponds to 20% and 90% enhancement when compared to plain glass and low-emissive glass substrates. This meta-glass possesses 86% peak optical transparency at $\lambda=550 nm$, $>$60% near-IR reflection, and $>$ 80% mid-IR reflection which corresponds to $\approx$ 0.2 thermal emissivity. The proposed metasurface design is highly flexible and can be tuned to operate over different frequency ranges owing to its frequency scalability. This study provides a better alternative using earth-abundant materials compared to low-emissive glass based on indium tin oxide (ITO) while boosting the efficiency of 5G communication amenable to window systems demanding simultaneous functionalities for emergent smart/energy-efficient buildings/cities and autonomous transportation applications.