Polarization and space multiplexing metasurface for high-efficiency holography.

Abstract

This paper presents a fast and efficient design method for generating multiplanar, dual-linearly polarized holographic patterns in the near-field of a Huygens metasurface when illuminated by incident waves with matching polarizations. The propagation kernel of the traditional Gerchberg-Saxton (GS) algorithm is modified to utilize Green's function (DGF), and a dynamic control factor is introduced to adjust the uniformity of the pattern amplitude. This modification results in an imaging phase distribution, hereby designated as the improved weighted Gerchberg-Saxton algorithm (GS-W). The use of a Huygens metasurface with high transmittance and large phase coverage increases the imaging efficiency of the incident energy, exceeding 32%. As proof of the concept, we fabricate the aforementioned meta-device, which contains 40 × 40 meta-atoms, each with a length and width of 6 mm (0.5λ at 25 GHz) and thickness in the longitudinal direction of 1.8 mm. Both the calculation and simulation results show that the quality factors of all reconstructed patterns can exceed more than 42%.