Multifunctional acoustic holography based on compact acoustic geometric-phase meta-array

Optical geometric-phase metasurface provides a robust and efficient means for light control by simply manipulating the spatial orientations of in-plane anisotropic meta-atoms, where polarization conversion plays vital role. However, concept acoustic modulation field remains unexplored because airborne waves lack similar optical process. In this work, new type meta-atom with deep subwavelength feature size is theoretically investigated further applied to engineering based on so-called geometric phase. Herein, tunable designated order obtained via near-field coupled orbital angular momentum transfer process, topological charge-multiplexed phase endows our meta-arrays multiple functionalities. Our work extends capacity in high-quality reconstruction offers possibilities multifunctional meta-holograms.