Helicity Multiplexed Spin‐Orbit Interaction in Metasurface for Colorized and Encrypted Holographic Display

The photonic spin-orbit interaction (PSOI) in inhomogeneous anisotropic metasurface has drawn much attentions recently due to its superior ability to manipulate light wave in the deep-subwavelength scale. Traditional methods involving PSOI are limited to operational spectral bandwidth owing to the intrinsic dispersion of the constitutive materials. In this paper, a helicity-multiplexing scheme is proposed to achieve independent control of the PSOI in both the spectral and spatial domains by combining the broadband characteristic with polarization dependence of the metasurface. Two simultaneous functions of multicolor holographic display and polarization encryption are experimentally demonstrated with a single metasurface perforated with nanoholes. Although the optical response of the nanoholes themselves are almost independent of the light wavelength, the obtained image can have abundant spectral information. The approach proposed here is promising for realizing multifunction optical device, multicolor display, optical storage and information encryption.