Fig. 2: Design and functional verification of dielectric metasurface.
a Amplitude and (b) phase retardation of cross-polarization after transmission through a periodic nanopillar array (h = 500 nm). The operational wavelength of the metasurface device is designed to be 650 nm. Dx and Dy represent the length and width of the cross-section of the nanostructure. Triangular symbols in the figure denote the selected nanopillars. c Calculated birefringent phase shifts, δx and δy, for different phase levels. Each distinct phase level is associated with a specific nanostructure, where each nanostructure serves the role of a birefringent nano-waveplate. d Simulated energy density of a representative nanostructure under circularly polarized light illumination. Top and side views of the normalized energy density in an infinitely periodic array. The dashed white lines depict the boundaries of the nanopillars. Scale bars represent 100 nm. e The collaborative mechanism of the different metasurface sub-arrays. The red lines represent the wave vectors provided by different metasurface sub-arrays for LCP and RCP light. f Normalized far-field intensity distribution of each metasurface sub-array under unpolarized plane wave incidence
