Figure 4

Near-field and far-field results of the proposed POPA. (a) The picture with colorbar depicts the intensity of E _z on the yoz plane. The curve is the intensity of E _z along the reference line 1 in Fig. 3b, i.e. along the bottom surfaces of the nanopatches. (b) Simulated normalized far-field directivity patterns at various wavelengths. The inset shows the comparison between the theoretically predicted and the numerically extracted phases of the radiated component, i.e. E _y component along the reference line 2 in Fig. 3c. The reference line 2 is 50 nm above the upper surfaces of the nanopatches. (c) Near-field distribution of E _y in the central plane of the array showing the forming of a directional power emission which originates from the coherent interference of the nanopatches. The central plane is the symmetry plane of the array and in parallel with the xoz plane. The results are obtained at 1550 nm. The animated result can be found in Supplementary Materials (Supplementary Video S2).