Multi-fold Phase Metasurface Holography Based on Frequency and Hybrid Decoupling Polarizations

Metasurfaces are artificially intelligent planar optical devices that can realize excellent functions by optimizing the design of nanostructures and arrays. Metasurfaces have become the preferred approach for fabricating integrated and compact optical systems with micro- and nano-scale solutions for realizing multi-dimensional modulated optical devices. Herein, the realization of multi-fold phase holography is demonstrated by combining switchable optical frequencies with hybrid circular and linear polarization states. The original holographic phase distribution can be inversely optimized using an adaptive momentum gradient descent algorithm. Furthermore, completely different images can be reconstructed when the phase values are several times the original values. The multi-fold phase modulation can be achieved by optimizing the structural distribution of the dielectric metasurface with the incident changeable light frequency and decoupled circular and linear polarization. Different polarization combinations enhance the flexibility of multiple holographic modulations. This technology provides new solutions for dynamic multi-fold beam directional refraction and excitation, orbital angular momentum communication, multi-fold holographic displays, optical encryption and camouflage, light switching, and shaping.