Figure 6

Profiles of the normalized |Ex| (dashed black line) and |Hy| (solid blue line) for SPPPs of the air/graphene/LiF/glass waveguide with t = 100 nm. (a) f = 8 THz, (b) f = 11 THz, (c) f = 18 THz, and (d) f = 20 THz. Glass substrate, LiF film, and air regions are highlighted in aqua, light brown and white, respectively. The graphene layer is schematically shown by solid black line at z = t/2.