Broadband transmissive amplitude-and-phase metasurface for vortex beam generation and hologram

•Transmissive metasurface controlling the phase and amplitude responses.•Generation of high-purity vortex beam in a wide frequency band.•Realization of metasurface holography with two imaging planes. Transmissive electromagnetic metasurfaces that allow for the independent and simultaneous control of the cross-polarized phase and amplitude responses are presented. On varying the square split ring opening and orientation angles, the cross-polarized transmission response allows for full phase and amplitude coverage and exhibits broadband characteristics. Because of the designed amplitude-and-phase units, the metasurfaces allow for complex field manipulations over a wide frequency band. Representative applications of the proposed metasurfaces include (1) the generation of a high-purity vortex beam (with Chebyshev amplitude distribution) and (2) the realization of metasurface holography with two imaging planes over a wide frequency band. The measurement results agreed well with those of full-wave simulations, thus confirming the feasibility and effectiveness of the proposed approach, which is suitable for designing advanced, broadband field-manipulation systems.