Figure 2
From: Hybridization of graphene-gold plasmons for active control of mid-infrared radiation
Design of the hybridized gold-graphene metasurface for detuned resonances. (a) Parameters of the metasurface: ax = 1210 nm, ay = 70 nm, cx = 270 nm, cy = 150 nm. The height h of the gold rods is 25 nm. Light is polarized along the x-axis (long axis of rods). (b) Calculated transmittance of the metasurface across the mid-infrared regime for various values of graphene’s Fermi level in eV. The gold and purple arrows depict “gold-like” and “graphene-like” resonances, respectively. Black dashed vertical lines indicate silica phonon lines. The damping parameter of graphene is 0.02 eV. (c) \(|{E}_{y}|\) map at 0 eV (d) and at 0.4 eV. Color bar values represent field enhancement. Scale bar (white) is 200 nm. (e) Charge density map calculated at 0.4 eV. (f) Cross section of charge density at x = 520 nm, along the black dashed line in (e). All maps shown are calculated on the graphene plane with excitation wavelength λ = 7.5 µm, corresponding to a purple arrow in (b) and with horizontally (x-axis) polarized incident light. The charge density oscillations in (e) are mostly concentrated on the graphene area, and the resonance character is essentially that of graphene plasmons.
