Surface Waves on Non-conducting Structured Interfaces

Surface waves are demonstrated theoretically to propagate along periodically corrugated surfaces made of non-conductive lossless materials with positive permittivity. An analytic derivation of the surface wave dispersion relation is presented in the case of the deeply subwavelength period of a corrugated structure using impedance boundary conditions (IBCs) at the interfaces. Thus obtained dispersion relation is verified numerically and limitations as well as the physicality of IBCs when modeling surface waves are discussed. Finally, suitable materials, potential experimental realization, and sensing applications of surface waves in the terahertz spectral range are discussed.