Fig. 1. Schematic diagram of the typical geometric phase-type building blocks and all-metal metasurfaces. The first and second quadrants show the metallic nanobrick and grating unit structures and the designed electromagnetic stealth devices^{[36, 46]}, holographic display device^[37], and vortex beam generator^[47]; the third quadrant shows a catenary metal unit structure and the designed circularly polarized beam splitter^[48], optical wave focusing device^[49]; the fourth quadrant shows the unit structure with multi-fold rotational symmetry and the designed wavefront modulation device^[50] and rotational Doppler effect detector^[51]

Fig. 2. Simulation results of different metal unit structures. (a) Simulation results of metal gratings^[36]; (b) Simulation results of metal nanobricks and comparison with MIM-type structure ^[37]; (c) Simulation results of S-type unit structure ^[47]; (d) Simulation comparison of different C3 structures ^[50]

Fig. 3. All-metal catenary metasurfaces. (a) Circular polarized beam splitter^[48]; (b) Focusing lens^[49]

Fig. 4. Multifunctional devices based on all-metal metasurfaces. (a, b) Simultaneous near-field grayscale display and three-dimensional holographic imaging enabled by complex amplitude modulation^[70]; (c, d) Simultaneous full-color printing and holography enabled by all-metal metasurface^[71]

Fig. 5. All-metal metasurfaces based on split-ring resonators. (a) Schematic diagram of the terahertz metasurface^[73]; (b-d) Simulation results of the terahertz metasurface, including anomalous reflection, focusing, vortex beam generation^[74]; (e) All-metal metasurface for simultaneous manipulation of electromagnetic waves and acoustic waves^[75]; (f-h) Calculations results of multiple-beam generation, scattering diffusion, and beam steering for both electromagnetic waves and acoustic waves^[75]

Fig. 6. Laser-infrared and microwave-infrared stealth technology based on all-metal metasurface. (a) Measurement results of the laser-infrared compatible stealth materials^[36]; (b) Equivalent circuit model of the thick metal grating and measured high-temperature RCS and infrared radiation of the microwave-infrared compatible stealth materials^[46]

Fig. 7. Multispectral compatible stealth metamaterials based on all-metal metasurfaces. (a) Schematic diagram and simulation results of the hierarchical metamaterial for laser-infrared-microwave compatible stealth^[83]; (b) Schematic diagram of the large-area and multiscale hierarchical metamaterials and experimental test results^84]; (c) Schematic diagram and experiment results of the flexible metallic metasurface for multi-wavelength lasers and infrared compatible stealth^[85]