Utilizing Pancharatnam-Berry-Phase Metasurface for Advanced Control in Waveplates, Beam Splitter and Flat Luneburg Lenses

We utilize metasurfaces to design, fabricate, and experimentally demonstrate a novel microwave device based on the Pancharatnam-Berry (PB) phase principle, marking the pioneering application of PB phase theory in Luneburg lens design. This innovative approach allows for the creation of versatile components such as half-wave plates, beam splitters, and Luneburg lenses. Simulation results indicate nearly 100% linear polarization conversion efficiency for the half-wave plate almost in the Ka frequency band, while actual measurements confirm efficiency exceeding 80% between 26 and 37 GHz. Leveraging half-wave plate meta-atoms, we integrate them with PB principles for beam splitters and Luneburg lenses, enabling precise reflection of incident waves at specific angles. This study validates the effectiveness of these metasurfaces through comprehensive simulation and measurement analyses across the Ka-band frequency spectrum, showcasing excellent reflection efficiency. These findings underscore the groundbreaking nature of applying the PB phase principle to Luneburg lens design, offering advanced performance in microwave applications and promising applications across various electromagnetic wave bands, potentially supplanting conventional optical lenses.