Terahertz pulse propagation using plasmon-polariton-like surface modes on structured conductive surfaces

The dispersion relation and confinement of plasmon-polariton-like terahertz surface modes sustained by a perfectly conducting planar surface patterned with a regular lattice of holes are studied using full-field three-dimensional numerical simulations. Edge coupling and subsequent surface guiding with subwavelength vertical confinement of the frequency components below the band edge of the surface mode is demonstrated for a broadband pulse with 0.5THz⩽f⩽2THz. Additionally, the constraints imposed by lattice constant and hole size on the creation of defect waveguides offering lateral confinement are discussed.