Polarization-switchable holograms based on efficient, broadband multifunctional metasurfaces in the visible regime

Gradient metasurfaces provide a novel approach to the phase manipulation of incident electromagnetic waves. Thus, they have the potential to create compact, light-weight optical solutions. An attractive feature of metasurfaces is the ability to integrate multiple optical functionalities into a single surface design. Here we demonstrate a high-efficiency (up to ~60%), reflective meta-hologram for visible light by using an ultra-thin (~λ/4 thick) gap surface plasmon-based metasurface. By precisely sampling the predesigned image phase and amplitude to the unit cells of our device, polarization-controlled dual images are reconstructed with a high polarization extinction ratio and high fidelity. The proposed technique expands the range of possibilities for high-quality hologram generation by using ultra-thin nanophotonic devices and paves the way for variousholography-related applications across the visible band.