Wideband millimeter wave absorber based on coding-metasurface with two-dimensional MXene

Abstract

This study investigated MXene ink as the absorbing material in a wideband millimeter wave (MMW), metasurface absorber and applied the ink in a periodic array. The MXene ink was characterized in the Ka-band, and a Debye permittivity model was found that accurately described the highly frequency-dependent properties. A 1-bit coding-metasurface algorithm was used to discover an optimized design that minimized the average reflectance at normal incidence, utilizing the unique properties of the materials. The absorber was fabricated using hybrid processing techniques and measured at multiple incident angles to compare against the simulated design. The absorber demonstrated a wideband response (i.e., 14 GHz bandwidth) at normal incidence with a greater than 93% absorptance from 26 GHz to 40 GHz and an average reflectance of 2% over the entire band. Furthermore, the absorber tested at a 10-deg incident angle demonstrated a greater than 91% absorptance at the Ka-band and an average reflectance of 3.4% across the band; Tested at a 20-deg incident angle, the absorber demonstrated a greater than 88.5% absorptance and an average reflectance of 3.9% across the band. The study established the value of using MXene ink in metasurface absorbers for wideband applications in MMW frequencies.