On‐Demand Dynamic Polarization Meta‐transformer

Abstract Polarization is one of the key characteristics of light; hence its versatile manipulation plays a pivotal role in wave‐matter interaction, communication, detection, etc. Although metasurfaces have emerged as a promising platform for polarization optics, most of them only support limited polarization controls even in reconfigurable fashion. Here, an on‐demand dynamic polarization meta‐transformer operating for full Poincaré sphere by means of an ultrathin transmissive time‐varying metasurface is proposed. By temporally and independently modulating co‐polarized transmission coefficients of the metasurface for a pair of orthogonal linearly polarized incidence, the effective transmission metasurface anisotropy can be modified to mimic the desired arbitrary birefringence, thus enacting the polarization transformation between incidence and transmission waves with arbitrary polarization states. Experiments have been conducted in the microwave region to verify the design theory. This study may provide a new architecture in polarization optics and may advance the applications in vectorial polarimetry imaging, polarimetry radars, and optical/wireless communications.