Tunable amplitude metasurface electromagnetic stealth material based on vanadium dioxide

With the rapid advancement of research on terahertz metamaterial absorbers, their significant value in the field of stealth technology has attracted widespread academic attention. In this paper, an electromagnetic stealth material based on a tunable terahertz metasurface is designed by leveraging the phase transition properties of vanadium dioxide (<i>V</i><i>O</i>₂). Compared to similar designs, it offers advantages including simple structural design, wider absorption bandwidth, superior absorption performance, and tunable functionality. The electromagnetic stealth material is composed of a periodic unit structure, each comprising a three-layer architecture in sequential order: a gold substrate as the bottom layer, a polymethacrylimide (PMI) dielectric layer in the middle, and a <i>V</i><i>O</i>₂ resonant array as the top layer. Numerical simulations show that this electromagnetic stealth material realizes ultra-wideband perfect absorption (<i>a</i><i>b</i><i>s</i><i>o</i><i>r</i><i>p</i><i>t</i><i>i</i><i>o</i><i>n</i><i>r</i><i>a</i><i>t</i><i>e</i>>90<i>%</i>) in the frequency band of 3.13 to 13.56 THz, with an absorption bandwidth reaching 10.43 THz. Additionally, the material features tunable absorption and polarization insensitivity. The electromagnetic stealth material not only exhibits excellent stealth performance but also breaks through the limitations of traditional stealth materials, realizing the function of artificial regulation of incident radiation absorption. This provides a new approach, to our knowledge, to the design of flexible electromagnetic stealth materials and paves the way for diversified technical approaches to adaptive terahertz systems in military applications (e.g., camouflage), stealth technology, and other related fields.