Fig. 2: The analysis of SH-GSL, designed meta-atoms, and the mirror mode.

a The schematic of the deterministic Floquet-engineered momentum compensation mechanism. By engineering the incident angle and compensation wave vector, each spatial harmonic can be confined in the plasmonic zone or radiative zone, thereby enabling different manipulations. b The relationship of the incident angle and the compensation wave vector. Different regions represent the radiative zones of different harmonics, and out-of-region means that the harmonic is localized on the surface. c The relationship of incident and reflective angles of different harmonics after designing the compensation wave vector (0.8k₀) of the metasurface. d The schematic of the meta-atom. e The amplitude and phase response of the meta-atom from 4 GHz to 24 GHz. f The amplitude and phase response of the meta-atom from L = 1.6 mm to L = 4.0 mm at 14 GHz. g The schematic of the supercell of the metasurfaces: dual-beam splitting, abnormal harmonics reflection, and three-channel retroreflection. h The illustration of the dominant area of the mirror mode, where the abnormal reflection is much lower than the mirror reflection. The analysis of different far-field patterns under i −13°, j −16°, and k −28° incidence, which represent the cases of dominant mirror reflection, mirror equal to abnormal reflection, and dominant abnormal reflection, respectively