Fig. 1. Schematic diagram of the mode-visualizing metasurface.

Fig. 2. Training architecture of the mode-visualizing metasurface.

Fig. 3. Structural design of the mode-visualizing metasurface. (a) Schematic of the nanostructure unit-cell. (b) Simulated optical responses of the nanostructure unit-cell. (c) Optimized phase profile. (d) Enlarged phase profile.

Fig. 4. Numerical simulation results of the mode-visualizing metasurface under x-polarized modes. The first and second rows show the input modes, simulated outputs, simulated targets, and designed targets for the LP₀₁ and LP₁₁ modes, respectively. The white boxes highlight the target images.

Fig. 5. Partial SEM images of the fabricated metasurface.

Fig. 6. Experimental results of the mode-visualizing metasurface. (a) Experimental setup to receive the holographic images. (b)–(g) Captured mode field, captured holographic image, and enlarged target image under LP₀₁ and LP₁₁ mode incidences.

Fig. 7. Quality evaluation of the target images. (a) Pearson correlation coefficients between the simulated and desired target images. (b) Pearson correlation coefficients between the experimental and desired target images. (c) Energy ratio between the target image of the incident mode and that of the other mode in the simulated holographic image. (d) Energy ratio between the target image of the incident mode and that of the other mode in the experimental holographic image.

Fig. 8. Numerical simulation results of mode-visualizing metasurface under y-polarized modes. The first and second rows show the input modes, simulated outputs, simulated targets, and designed targets for the LP₀₁ and LP₁₁ modes, respectively. The white boxes highlight the target images.