All-in-one modular metasurfaces enabling multiparameter manipulation and function switching

Controlling the amplitude, phase, and polarization of electromagnetic waves is essential for multifunctional metasurfaces; however, conventional designs become exponentially more complex as additional functionalities are added. Here, we present a modular approach to a universal, multifunctional polarization controller that combines wavefront, phase, and polarization manipulation. First, we propose a set of chiral enantiomer metasurfaces for polarization conversion, and these are then combined with phase-gradient metasurfaces to construct dual-functional modules. These modules enable simultaneous wavefront shaping and polarization conversion with over 95% efficiency across a 27.6% relative bandwidth from 9.7 to 12.8 GHz. Our experimental results demonstrate that cascading the modules at optimized distances with mechanical rotations achieves broadband control over the wavefront, polarization, and amplitude. This includes linear and circular polarization beam splitters with a conversion efficiency greater than 90% and an axis ratio below 3 dB, neutral-density-filter-like devices with tunable transmittance ranging from 0% to 90%, and arbitrary polarization rotators spanning from 0° to 180°. The architecture enables reconfigurable functionality without active components, relying on Fabry-Pérot interference and spatial arrangement. This work establishes a paradigm for compact electromagnetic systems with applications in beam steering and adaptive optics and paves the way for industrial adoption through simplified fabrication.