Fig. 3

FDTD-simulated E _z electric field component distributions for the device. (a), (b) E _z electric component distribution in x–y plane 200 nm below the metamaterial layer for E _x polarization at 10.7 μm (panel (a)) and E _y polarization at 10.3 μm (panel (b)), respectively. (c), (d) E _z electric component distribution in x–z and y–z planes at y = 0 and x = 0 for E _x polarization at 10.7 μm (panel (c)) and for E _y polarization at 10.3 μm (panel (d)), respectively