Figure 1
From: Challenges in nanofabrication for efficient optical metasurfaces
(a) Scattering cross-section of an isolated silicon nanocylinder (\(H = 170\ \hbox {nm}\), \(D =160\ \hbox {nm}\)). The full line shows the total scattering cross-section whereas the orange dotted (resp. green dashed) line is the contribution from the electric (resp. magnetic) dipolar resonance only. (b) Deflection of a plane electromagnetic wave by a metadeflector: The phaseshift induced by the dielectric nanoresonators varies along the surface yielding a global tilt of the exit wave by an angle \(\theta _d\). The metadeflector is composed of several supercells composed of \(N_d\) resonators. Over the supercell length \(l_c\) an incident plane wave experiences a \(2\pi\) phaseshift. (c) A plane wave incident on a metadeflector is split into several output beams. The deflected beam carries nearly all the transmitted power. Transmission efficiency (d) and dephasing (e) of a \(\lambda _{c}= 750\ \hbox {nm}\) plane wave normally incident on an infinite square array of silicon nanocylinders with constant height \(H = 370\ \hbox {nm}\). The white dashed line corresponds to the lattice spacing chosen in the following. (f) Polar plot showing the transmission and dephasing of a \(\lambda _c =750\ \hbox {nm}\) plane wave normally incident on a periodic array of identical nanocylinders with selected diameters. The height and spacing are the same for all nanocylinders (\(H=370\ \hbox {nm}\) and \(a =300\ \hbox {nm}\) respectively). The transmission and dephasing are respectively given by the distance to the center and angle.
