Controllable propagation of vector beams guided by a metasurface

Vector beams with controllable trajectories are beneficial to practical applications. This paper proposes a technique to control the propagation of parallel vector beams based on a holographic metasurface. The metasurface consists of identical A-Si nanopillars fused on glass substrate. The generated vector beams may propagate along the defaulted trajectory, and their trajectories may be straight or winding. The designed metasurface not only realizes the manipulation of the in-plane state of polarization but also achieves the propagation control of vector beams. The simulated and measured results for vector beams with their orders and propagation trajectories varying verify the performance of the designed metasurface. The generation of vector beams with the parallel output, the controllable order, and the customized trajectory can bring more convenience and possibilities for the applications of vector beams.