Dielectric Polarization‐Filtering Metasurface Doublet for Trifunctional Control of Full‐Space Visible Light

Abstract Multilayered plasmonic metasurfaces have been previously shown to enable multifunctional control of full‐space electromagnetic waves, which are of great importance to the development of compact optical systems. While this structural configuration is practical for acquiring metasurfaces working in microwave frequency, it will inevitably become lossy and highly challenging to fabricate when entering the visible band. Here, an efficient yet facile approach to address this issue by resorting to a dielectric metasurface doublet (DMD) based on two vertically integrated polarization‐filtering meta‐atoms (PFMs) is presented. The PFMs exhibit polarization‐dependent high transmission and reflection, as well as independent and full 2π phase control characteristics, empowering the DMD to realize three distinct incidence‐direction and polarization‐triggered wavefront‐shaping functionalities, including anomalous beam deflection, light focusing, vortex beam generation, and holographic image projection as it is investigated either numerically or experimentally. The presented DMD undoubtedly holds several salient features compared with the multilayered metallic metasurfaces in aspects of design complexity, efficiency, and fabrication. Furthermore, as dielectric meta‐atoms with distinct polarization responses can be deployed to construct the DMD, it is anticipated that diverse full‐space metasurfaces equipped with versatile functionalities can be demonstrated in the future, which will greatly advance the development of multifunctional meta‐optics.