Abstract:
The on-chip metasurface is introduced into integrated optical waveguides to achieve arbitrary modulation of guided waves, which provides a convenient and versatile platform for the conversion between guided waves and free-space functions. Despite previous explorations in on-chip holography demonstration, it still faces critical challenges to expand the encoding freedom and multiplexing. Here, we propose and experimentally demonstrate a quad-fold multiplexed holographic display optics device based on an on-chip metasurface. By mixing the detour phase and Pancharatnam-Berry (PB) phase, the on-chip metasurface couples the guided waves into free space in circular polarization, destroying the phase degeneracy that exists in the wavevector directions with only the detour phase. Moreover, by utilizing simulated annealing phase optimization algorithm and multiplexing, we achieved a quad-fold multiplexed far-field holographic display with independent encoding capability. The proposed method in this paper opens up a new prospect for multifunctional integration of on-chip metasurfaces and provides an alternative approach for integrated optical communication with high information storage capacity.