Flexible Multiplexing of High-order Poincaré Sphere Beams with Reflective Metasurface

In this paper, a new methodology to realize flexible multiplexing of high-order Poincaré sphere beams by a reflective spin-decoupled metasurface is proposed. By integrating geometric phase and propagation phase, the proposed metasurface can offer more potential in controlling the vector vortices, addressing the problem of topological charge correlation that exists in metasurface with only geometric phase. As the design example, we present that two off-axis high-order Poincaré sphere beams can be achieved by a single metasurface in microwave region. The results pave a way for generating versatile vector vortices using spin-decoupled metasurface.