Multilayer enhanced metasurfaces with high efficiency and additional functionalities

Efficiently controlling the propagation of light is a most important issue in the optics. The traditional optical elements manipulate light by phase accumulation through light propagation. Metasurfaces, serving as nanoscale phase shift, have attracted the interest because they possess the ability offering fascinating possibilities to realize unprecedented photonic phenomena while interact with light over the scale of the wavelength. Although kinds of novel functionalities are reported, monolayer metasurfaces and hybrid metasurfaces are limited by their less geometric structure parameters. Since the hybrid multilayer metasurfaces have more adjustable parameters, expanding the capacity to control the light beam, we use the hybrid multilayer metasurfaces to realize polarization-insensitive anomalous reflection and polarization-sensitive focusing. The gradient metasurface exhibits high efficiency anomalous reflection for both x-polarized and y-polarized light. The metalens has opposite focus for right-handed circularly polarized and left-handed circularly polarized incident light. The results may offer some help to find various potential applications in nanophotonics.