Topological Polar Microdomains Enabling Spatial Light Field Manipulation

Topological polar textures in ferroelectric oxides exhibit diverse spatial dipole-moment configurations, holding great potential for innovative spatial light field manipulation through effective light-matter interactions. However, conventional topological polar textures are typically on the nanometer scale laterally, making them unsuitable for spatial light field manipulation of laser beams. Here, we report the design of topological domains on the micrometer scale using freestanding BaTiO₃ membranes and demonstrate their feasibility in spatial light field modulation. By introducing dome-shaped microstructures in BaTiO₃ membranes, we create a radial flexoelectric field through lattice distortion, which in turn induces center-convergent topological microdomains. The interplay between the topological dipole distributions and light promotes the conversion of circularly polarized waves into vortex light fields via nonlinear spin-to-orbit angular momentum conversion. Further dynamic manipulation of vortex light fields is also achieved by thermally and electrically switching the polar topology. Our work highlights the vast potential of abundant topological polar textures in advanced light field modulation, with promising applications in highly integrated photonic circuits and reconfigurable high-capacity optical communications.