Independent Energy Allocation of Dual-Helical Multi-Beams with Spin-Selective Transmissive Metasurface

Although metasurfaces have provided unprecedented control of electromagnetic (EM) waves, it is still challenging for the arbitrary manipulation of spatial radiation modes, energy distribution, and spin state of EM wave especially in microwave frequencies. Here, a cascaded dual-helicity-decoupled transmissive metasurface to realize independent modulation of two orthogonal circularly polarized waves is proposed. Leveraging this appealing feature, distinct multiple beams with freely designed energy intensities for two spin states generated from a metasurface are demonstrated experimentally with high efficiency, providing full control of sophisticated wavefronts, spin states, and their energy allocations. Two proof-of-concept designs are implemented in microwave region, which may offer a new way to achieve spatially energy-editable multifunctional devices that can be used in practical applications, such as beam forming, multiple target tracking, and wireless communications.