Fig. 1. Two-dimensional code metasurface PBS based on gradient index^[22]

Fig. 2. Transmittance of two types of polarized light at different output ports as a function of wavelength^[22]. (a) TM; (b) TE

Fig. 3. SEM images of optimization results of EBL and ICP processes. (a) SEM image of EBL exposure results; (b) SEM image of EBL exposure result details; (c) SEM image of ICP etching results

Fig. 4. Manufacturing process diagram of metasurface polarization beam splitter

Fig. 5. SEM images of the preparation results of the metasurface polarization beam splitter. (a) Overall SEM image of polarization beam splitter and coupling grating; (b) overall SEM image of metasurface structure; (c) SEM image of metasurface sub-wavelength structure details; (d) SEM image of metasurface etching depth

Fig. 6. Schematic diagrams of the testing experimental setup. (a) Standard testing bench; (b) side view of fiber optic coupling; (c) top view of coupled grating testing; (d) top view of metasurface polarization beam splitter testing

Fig. 7. Experimental test results of transmittance of two types of polarized light at different output ports as a function of wavelength. (a) TM; (b) TE