Polarimetric Metagrating-Assisted One-Step Multi-Dimensional Sensing Using a Vector Vortex Beam

Multidimensional optical sensing requires compact methods capable for jointly retrieving spatial, angular, and polarization-resolved information from structured optical fields. Here, we present a one-step multidimensional sensing approach in which vector vortex beams (VVBs) serve as optical probes, whereas a polarimetric metagrating simultaneously analyzes their intensity and polarization responses to radial and angular variations. Theoretical and experimental investigations of the topological charge l and polarization order m reveal their distinct governing roles, establishing a parameter-space framework that links intrinsic VVB properties to measurable radial and polarization-dependent angular features. The polarimetric diffraction orders reconstruct the full-Stokes parameters and reveal a periodic angle-of-polarization distribution governed by 2m, whereas the polarization-insensitive central order preserves the VVB intensity morphology and yields a dark-core radius with a square-root dependence on l. Measurements with linearly and elliptically polarized VVBs demonstrate an experimentally distinguishable angular change of approximately 2°. Using the polarization-insensitive central diffraction order for radius sensing extends the metagrating beyond polarization analysis and broadens its functionality in diverse polarimetric scenarios. The integration of the topological and polarization degrees of freedom of VVBs with chip-scale full-Stokes polarimetry establishes a compact and robust platform for vector-beam diagnostics, structured-light state recognition, optical mode monitoring, and polarization-dependent rotation sensing.