Analysis of Quasi-Periodic Effect in the Design of the Nanorod Metasurfaces

Periodic boundary condition is commonly implemented in element simulation for metasurface design. However, the actual boundary condition deviates from this assumption. This results in phase error from the design. This paper offers a theoretical analysis of the quasi-periodic effect of the nanorod metasurface. Efficiency and element phase error of the metasurface are both studied to evaluate the quasi-periodic effect. The result shows that quasi-periodic effect can induce phase error up to 80 degrees, and efficiency of the metasurface decreases up to 40%.