Multifunctional dielectric terahertz metasurfaces via spin-decoupled phase control

Integrating multiple functionalities into a single device is a striking field in metasurfaces. Here, we experimentally demonstrate several efficiently multifunctional dielectric metasurfaces in the terahertz regime using a spin-decoupled phase control method allowed by simultaneous control of dynamic phase and geometric phase. The designing strategy shows an impressive robustness and a great flexibility in designing metasurface-based multifunctional devices, and opens new avenues toward the applications in beam steering and polarization multiplexing.