Nonlinear spoof surface plasmon polariton phenomena based on conductor metamaterials

We present nonlinear phenomena produced from spoof surface plasmon polariton (SSPP) modes. Below the THz spectrum, artificially textured conducting metastructures on a subwavelength scale generate surface-bound modes and are called SSPP modes, similar to surface plasmon polariton (SPP) modes in the visible spectrum. Even though nonlinear effects in the THz domain are negligible, subwavelength metallic gap structures are ideal candidates to realize nonlinear behavior in the THz domain because of slow light propagation, strong electromagnetic confinement, and a high quality factor Q. In particular, when SSPP structures are combined with Kerr nonlinear materials, nonlinear-bistable curves can be observed below the THz spectrum.

► The basic properties of spoof surface plasmon-polariton (SSPP) modes are discussed theoretically and numerically.
► The SSPP architecture provides a high Q factor, strong light localization and an enhanced slow down factor.
► The nonlinear phenomena produced from spoof surface plasmon-polariton modes are discussed.
► The bistable curves can be achieved by using SSPP modes.
► The approach based on waveguide–cavity–waveguide can be applied to nonlinear bistable switches.
► Nonlinear bistable curves are highly robust against geometrical and material fluctuations.