Planar Metasurface Design for Wide-Angle Refraction Using Interface Field Optimization

Wide-angle planar metasurface refractors are designed by synthesizing complete interface fields corresponding to passive and lossless characteristics. To the Floquet modes associated with a refraction function, additional Floquet mode contents are introduced to the inner and outer layers, and optimized to render all admittance sheets between layers purely reactive. For optimized three-layer designs, full-wave simulations show perfect refraction without reflections. Analysis of physical three-layer metallic sheet designs shows high-efficiency refraction without supercell-level optimizations.