Accurate energy allocation and full polarization multiplexing of Airy beams using anisotropic metasurfaces

As an artificial two-dimensional (2D) metamaterial, metasurface has been widely studied for its ability to regulate electromagnetic waves through simple structures. However, traditional metasurfaces make it difficult to modulate different polarizations by a single device, let alone the reasonable allocation of energy to multiplexed polarizations, which is not suitable for comprehensive applications in multifunctional integrated system. Here, a full polarization multiplexing scheme and power-target-field-based addition theory for multiple beams, and an interference reduction scheme are theoretically proposed and experimentally achieved using anisotropic metasurfaces. The full polarization multiplexing scheme achieves different linearly polarized and circularly polarized beams using the same feed and tensor units with a simple design for the first time. The proposed addition theory modifies the existing scheme to achieve performance improvement and accurate energy allocation for multiple beams. The interference reduction scheme can control the propagation orientation and initial position of multiple beams, and finally achieve multi-dimensional control. All methods are verified by achieving 2D Airy beams, and the relationship between modulation function and the surface impedance that reflects material characteristics is studied. The anisotropic metasurfaces provide multiplexing functions using multiple beams with orthogonal polarization states and controllable power levels, which represents a simple and effective transmitting end for multi-functional systems and multiple targets in wireless transfer systems.