Compact spin-decoupled metasurfaces for polarization texture reconfiguration of Bessel–Gaussian vector beams during propagation

In this work, we introduce and experimentally validate a novel class of spin-decoupled metasurfaces enabling controlled evolution of polarization textures of Bessel–Gaussian vector beams along the propagation direction. Unlike conventional approaches that produce static field distributions, the proposed flat optical platforms encode independent phase profiles for the two orthogonal circular polarization states (left- and right-handed). This capability allows the direct generation of dynamic propagation effects, including polarization beating, topological transitions, and oscillatory local non-separability, thereby enabling effective spatial reconfigurabilty and control. The experimental results are in excellent agreement with theoretical predictions, demonstrating that a single metasurface can achieve complex functionalities that typically require cascades of many standard optical elements and interferometric architectures, significantly improving compactness, alignment, and overall efficiency. The proposed framework paves the way for versatile, high-performance structured-light applications in compact photonic systems, with potential impact on optical manipulation and information and communication technologies.