Fig. 1. Three-dimensional structure of metasurfaces and the material parameters of VO₂. (a) Schematic diagram of the 3×3 array structure of the metasurface; (b) unit structure diagram; (c) curves of VO₂ electric conductivity varying with temperature; (d) relationships between n₀ and k of VO₂ in the dielectric state and wavelength; (e) relationships between n₀ and k of VO₂ in the metallic state and wavelength

Fig. 2. Perfect sbsorption spectrum and its electric field diagram. (a) Optical perfect absorption spectra and reflection intensity of metasurface structure under circularly polarized light illumination; (b) electric field component distribution at 490 nm; (c) electric field component distribution at 798 nm; (d) electric field intensity distribution at 490 nm; (e) electric field intensity distribution at 798 nm

Fig. 3. When VO₂ in the dielectric state, the intensity distributions of anomalous reflected light and normal reflected light in each direction are as follows. (a) Reflection intensity of the diffraction orders (0, 0), (1, 0), (-1, 0), (0, 1), and (0, -1); (b) total reflection intensity and conversion efficiency, the illustration showing the normalized intensity distribution of reflected light at wavelength of 750 nm

Fig. 4. (0, 1) order anomalous reflection phenomenon. (a) Anomalous reflection intensity and phase at the (0,1) order; (b) distribution of anomalous reflection angles as a function of wavelength

Fig. 5. Influence of the thickness h and structural period P of the metasurface on the (0,1) order anomalous reflection. (a) Anomalous reflection intensity under different h; (b) effective working bandwidth of anomalous reflection under different h; (c) anomalous reflection intensity under different P; (d) effective working bandwidth of anomalous reflection under different P

Fig. 6. Influence of the width w and length L of the metasurface on the (0,1) order anomalous reflection. (a) Anomalous reflection intensity under different w; (b) effective working bandwidth of anomalous reflection at different w; (c) anomalous reflection intensity under different L; (d) effective working bandwidth of anomalous reflection at different L