Polarization-Multiplexed Holography Based on Dielectric Metasurfaces

We present a silicon-nanobrick metasurface for dual-channel polarization-multiplexed holography at 1.55 μm. A Jones-matrix design combined with a Fresnel-based Gerchberg-Saxton algorithm maps the target phase profiles to nanobrick dimensions and orientations, enabling combined propagation-phase and geometric-phase control. Numerical simulations demonstrate holographic reconstruction for orthogonal linear, circular, and elliptical polarization pairs. The selected meta-atoms exhibit simulated power transmittances above 70% along both principal axes under periodic boundary conditions. The circular-polarization design is fabricated using electron beam lithography and hard-mask etching, and polarization-selective far-field reconstruction is experimentally observed. Further numerical analysis demonstrates continuous variation of the relative reconstructed intensities along an incident-polarization trajectory. Under an ideal collection and analyzer model, separately optimized elliptical analyzers provide central-signal suppression of 19.02 and 18.78 dB while retaining 64.30% and 61.71% of the corresponding target-image signals. An additional simulated design reconstructs two images within the same spatial region, yielding polarization-channel extinction ratios of 9.30 and 9.33 dB under fixed circular-analyzer conditions. These results demonstrate a silicon-based implementation of dual-channel holographic encoding and provide quantitative characterization of polarization-selective readout.