Subwavelength Custom Wavefront Shaping by a Nonlinear Electro-optic Spatial Light Modulator

Abstract

Holographic displays offer a method to completely reconstruct any desired wavefront and can thus lead to breakthrough innovation in beamforming, sensing, and information encryption. However, full control over a wavefront in the visible requires features of 100 nm or less. Here, we apply these stringent requirements in an all-encompassing device structure including light source, modulator, and driver electronics. To this end, we propose a continuous electro-optically modulated barium titanate slab waveguide employing a metamaterial cladding layer enabling electrodes to be in contact with the optically active layer. This prevents both the undesired scattering and the absorption that metallic electrodes would introduce. We elaborate the driving requirements of the proposed waveguide display including the optimal use of a nonlinear barium titanate crystal and electrical and optical simulations that show complete control over a waveguided mode, resulting in desired holographic imaging in far-field simulations.