Figure 1
From: Investigation of mechanism: spoof SPPs on periodically textured metal surface with pyramidal grooves
(a) The sketch of the SSPPs waveguide with periodic pyramidal grooves that consist of N rectangular grooves. (b–d) Front views of a unit cell of the waveguides with upright pyramidal grooves (b), rectangular grooves (c) and downward pyramidal grooves (d). (e) The waveguide sketch when N = 2.
