Figure 6

3D–FDTD simulated electric field patterns of (A–C) X–polarization and (D–F) Y–polarization of the 111, 212 and 222 NAs, respectively. (A,D) 111 NAs, (B,E) 212 NAs and (C,F) 222 NAs. The electric field patterns have been normalized, in which 1 and 0 represent the strongest and the weakest electric field enhancement.