Fig. 1. Schematic diagram of derivation of generalized law of refraction^[16]

Fig. 2. Structural diagrams and phase of metasurface resonance cell. (a) Structure of metasurface resonance cell; (b) 2D cross section; (c) phase distribution

Fig. 3. Phase delay curve of silicon nano-beam

Fig. 4. Structural diagram of gradient metasurface

Fig. 5. Simulated phase distribution and deflection efficiency of plane-wave passing through gradient metasurface. (a) Distribution of phase; (b) deflection efficiency

Fig. 6. Far-field distribution for different cell numbers n (take deflection angle of 30° as an example)

Fig. 7. Relationship between deflection angle θ and size d for normal incident light

Fig. 8. Effect of number of period on far-field divergence angle (take deflection angle of 30° as an example)

Fig. 9. Far-field distribution for different deflection angles

Fig. 10. Far-field divergence angle for different deflection angles

Fig. 11. Influence of relative deviation of W and H on deflection effect

Fig. 12. Influence of divergence angle of incident light on divergence angle of deflected light

Fig. 13. Influences of different wavelengths on beam deflection

Fig. 14. Schematic diagram of angle scanning