Multi-mechanism-empowered single-functional-layer metasurface simultaneously with microwave scattering reduction, infrared digital camouflage, and optical transparency

Abstract

The high degree of freedom of multimechanism metasurfaces has greatly facilitated multifunction or even multiphysics design for practical applications. In this work, to achieve camouflages simultaneously in microwave, infrared, and optical regimes, we propose a multimechanism-empowered metasurface composed of four elemental indium-tin-oxide-based meta-atoms. Each meta-atom can modulate microwaves both in phase and magnitude through polarization conversion and resonance absorption, which can realize radar stealth at 8–14 GHz. The reflective amplitude is less than −10 dB . When the incident angle increases to 60°, the reflective amplitude is still less than −3 dB . The far-field scattering patterns of microwaves are modulated by destructive interferences of reflected waves, which results in diffusion-like scattering due to randomly distributed reflection phases on the metasurface. The superposition of microwave absorption and diffuse reflection enables broadband microwave scattering reduction of the metasurface. Meanwhile, the emissivity of four types of meta-atoms covers from 0.3–0.8 at 3–14 μm due to delicately designed occupation ratios. The infrared radiation of the metasurface exhibits the characteristics of digital camouflage in infrared imaging. To demonstrate this method, prototypes were fabricated and measured. The measured results are consistent with the simulated ones. The angular stability in the microwave range within 0°–60° was also demonstrated. This work presents an approach to achieving multispectrum functions with integrated multimechanisms in a single functional metasurface layer and offers a new methodology for custom-designing infrared performance. Moreover, the simplicity of the structure offers significant cost control and large-scale fabrication advantages.

Topics & Concepts