Terahertz metasurface polarization detection employing vortex pattern recognition

The manipulation and detection of polarization states play a crucial role in the application of 6G terahertz communication. Nonetheless, the development of compact and versatile polarization detection devices capable of detecting arbitrary polarizations continues to be a challenging endeavor. Here, we demonstrate a terahertz polarization detection scheme by performing mode purity analysis and multidimensional analysis of the transmitted vortex field. The power of the proposed polarization recognition is verified by using three polarization trajectories, including linear polarizations, circular polarizations, and elliptical polarizations. Using the reconstructed complete polarization parameters, the detected polarization states are characterized using polarization ellipses, Poincaré sphere, and full-Stokes parameters. The experimental results validate the power of this scheme in polarization detection. This scheme holds promise for applications in polarization imaging and terahertz communication.