Optically Transparent Microwave Shielding Hybrid Film Composited by Metal Mesh and Graphene

Abstract

Transparent conducting materials with the ability of broadband electromagnetic shielding have a widespread range of applications in aerospace, medical equipment, and electronic communications. Achieving enhanced electromagnetic shielding effect without sacrificing much optical transparency is the technical trend in both academia and industries. Here, we experimentally propose a flexible hybrid film constructed by nano-printing based metal meshes and a graphene coating for the transparent electromagnetic shielding application. Numerical analysis is carried out to investigate optimal balance between electromagnetic shielding and optical transparency. In the experiment, enhanced shielding ability of hybrid film is observed without excessively sacrificing optical transmittance, compared to the reference group (the case only with metal mesh). Our work provides a hybrid platform for the high-performance optically transparent shielding materials for electromagnetic environment safety protection.

Single-Layer Achiral Metasurface with Independent Amplitude–Phase Control for Both Left-Handed and Right-Handed Circular Polarizations

“…Metasurfaces, the artificial planar arrangements of various subwavelength resonators, possess exceptional capability of tailoring the amplitude, phase, and polarization of electromagnetic waves. − Given the merits of low loss, small size, and simple fabrication, metasurfaces have drawn great attention and shown versatile applications, such as vortex beam generators, , focusing lenses, , meta-holograms, − surface plasmon polariton couplers, , etc. − Notably, some efforts are devoted to construction of chiral metasurfaces to acquire desired chiral effects. − For instance, numerous transmission-reflection-selective chiral structures are designed to block one state of the CP waves and transmit orthogonal CP waves. − Some ingenious metasurfaces can achieve circular dichroism by devising the chiral structures or introducing loss resistors into meta-atoms. − Furthermore, a range of schemes are proposed to independently control the wavefronts of LCP waves and RCP waves based on the integrated design of scaling-induced propagation phases and rotation-induced geometric phases. − More strikingly, certain multilayer multifunctional metasurfaces are established to tailor the amplitude and phase of orthogonal CP waves utilizing chiral structures with unequal dimensions working at distinct frequencies. , Nevertheless, most of the existing paradigms increase the complexity of the structures to obtain the intrinsic chirality or combine multilayer achiral structures to get the external chirality, and it is difficult for chiral metasurfaces to manipulate the amplitude and phase of orthogonal CP incident waves independently at the same frequency based on the present design mechanisms. In contrast, there are few studies on chiral phenomena generated by single-layer achiral structures, which means that the immense potential of chiral effects lies in simple achiral structures.…”

Recent advances of transition radiation: Fundamentals and applications

“…Due to the recent advent of two-dimensional materials (e.g. graphene [201][202][203][204][205][206][207][208], hBN [209][210][211][212][213][214][215][216][217], twisted photonic structures [218][219][220][221][222][223][224][225][226][227]) and metasurfaces [89,[228][229][230][231][232][233][234][235], the boundary is uniquely featured with a surface conductivity, which can be rather complex but provide an extra degree of freedom to regulate the free-electron radiation. Without loss of generality, the boundary with a non-zero surface conductivity is termed as the meta-boundary in Fig.…”

Perspective on Meta-Boundaries

“…Apart from individual meta-boundary, multiple meta-boundaries can be combined, which may induce the in-plane or out-of-plane interactions between neighboring meta-boundaries. Due to the rich yet relatively less explored physics in these in-plane and out-of-plane interactions, the exploration of multiple meta-boundaries is becoming another research tendency. − …”