Graphene-Based Optically Transparent Metasurface Capable of Dual-Polarized Modulation for Electromagnetic Stealth

Abstract

Microwave stealth technology with optical transparency is of great significance for solar-powered aircrafts (e.g., satellites or unmanned aerial vehicles) in increasingly complex electromagnetic environments. By coating them with optically transparent absorbing materials or devices, these large-sized solar panels could avoid detection by radar while maintaining highly efficient collection of solar energy. However, conventional microwave-absorbing materials/devices for solar panels suffer from bulky volume and fixed stealth performance that significantly hinders their practicality or multifunctionality. Particularly, dynamic modulation of microwave absorption for dual polarization remains a challenge. In this paper, we propose the design, fabrication, and characterization of an optically transparent and dynamically tunable microwave-absorbing metasurface that enables dual modulations (amplitude and frequency) independently for two orthogonal linearly polarized excitations. The tunability of the proposed metasurface is guaranteed by an elaborately designed anisotropic meta-atom composed of a patterned graphene structure whose electromagnetic responses for different polarizations can be dynamically and independently controlled via bias voltages. The dual tunability in such a graphene-based absorbing metasurface is experimentally measured, which agrees well with those numerical results. We further build an equivalent lumped circuit model to analyze the physical relation between the tunable sheet resistance of graphene and the polarization-independent modulations of the metasurface. Taking into account the advantages of optical transparency and flexibility, the proposed microwave-absorbing metasurface significantly enhances the multitasking stealth performance in complex scenarios and has the potential for advanced solar energy devices.

Multifunctional Graphene Metasurface for Highly Flexible Control of Microwave Absorption

“…The chemical potential μ c influences the R significantly, and the dynamic values will range from 170 to 2300 Ω, while X is close to 0. The chemical potential μ c of graphene can be regulated by the biased voltage on it . Here, graphene is considered as a resistive film material with variable surface resistance R in the frequency band 0–35 GHz.…”

“…The chemical potential μ c of graphene can be regulated by the biased voltage on it. 39 Here, graphene is considered as a resistive film material with variable surface resistance R in the frequency band 0−35 GHz. Figure 1f shows the principle of dynamically regulating the sheet resistance of graphene films.…”

Review of Broadband Metamaterial Absorbers: From Principles, Design Strategies, and Tunable Properties to Functional Applications

“…The optically transparent graphene‐based hypersurface with high absorption in the microwave band proves its potential application for radar stealth. [ 419 ] Furthermore, a BMA composed of graphene spheres can reach an average absorption of 97.4% in the wavelength region of 350–2500 nm. [ 420 ] In addition, graphene‐based holes also play an essential role in achieving broadband and wide‐angle absorbers.…”

“…2D Materials: 2D materials are commonly used to construct BMAs, and graphene is chosen as a typical representative of 2D materials in this section. [402,[418][419][420][421] This is because graphene can change the Fermi energy level by applying a bias voltage, which can electrically tune the BMAs (Section 4.3). Here, a few examples of BMAs realized using graphene will be highlighted.…”

A visible-near-infrared transparent miniaturized frequency-selective metasurface with a microwave transmission window

“…In recent years, with the rapid development of metamaterials [1][2][3][4] and metasurfaces, [5][6][7][8][9] artificial electromagnetic metamaterials have been widely employed to modulate electromagnetic waves, [10][11][12][13][14][15] elastic waves, [16][17][18][19][20] and acoustic waves. [20][21][22][23][24] The construction of metasurfaces with frequencyselective characteristics is a great challenge in the field of satellite communication and antennas.…”