Fig. 8
From: Recent advances in multi-dimensional metasurfaces holographic technologies
Janus and bilayer metasurfaces holography. a Direction-controlled polarization-encrypted data storage based on Janus metasurface composed of two enantiomeric plasmonic helical nanoapertures. Experimental results of the Janus metasurface in both the forward and backward directions for various incident polarizations are shown on the bottom [110]. b Simulated and experimental results of proposed directional Janus metasurface observed at different observation planes at 8.6 GHz for forward and backward waves [111]. c Schematic illustration of cascaded two-layer polarization sensitive meta-hologram. The unit-cell composed of L shape antenna and dimer layer are shown on the top [112]. d Schematic of multi-wavelength holograms, multi-wavelength waveplates, and 3D holograms based on dielectric bilayer metasurfaces [113]