Fig. 1. Schematic of unit structure of infrared ultra-wideband absorber

Fig. 2. Dielectric permittivity versus wavelength for TiO₂, NaF and VO₂. (a) TiO₂; (b) NaF; (c) real part of dielectric permittivity of VO₂; (d) imaginary part of dielectric permittivity of VO₂

Fig. 3. Polarization sensitivity of absorber. (a) Absorptivity versus wavelength for TE wave and TM wave at zero-degree incidence; (b) absorptivity as a function of azimuth angle and wavelength

Fig. 4. Absorptivity as a function of incident angle and wavelength. (a) TM wave; (b) TE wave

Fig. 5. Normalized electric and magnetic field profiles in x-y and x-z planes at three absorption peaks p₁, p₂ and p₃ when TE and TM waves are vertically incident. (a) Electric field of TE wave in x-y plane; (b) magnetic field of TE wave in x-y plane; (c) electric and magnetic fields of TE wave in x-z plane; (d) electric field of TM wave in x-y plane; (e) magnetic field of TM wave in x-y plane; (f) electric and magnetic fields of TM wave in x-z plane

Fig. 6. Relative impedance of absorber versus wavelength

Fig. 7. Absorptivity curves and corresponding magnetic field distributions under different structural parameters

Fig. 8. Effect of conductivity of VO₂ on absorption spectrum

Fig. 9. Comparison of absorption effects with and without pattern in TiO₂ layer when TE wave is incident