Simultaneous low-loss and low-dispersion in a photonic-crystal waveguide for terahertz communications

Conventional photonic-crystal waveguides make use of an equilateral triangular lattice of through holes, here we develop an isosceles triangular lattice photonic-crystal waveguide based on a silicon slab at 0.3 terahertz (THz) band, for THz high-speed communications. The propagation loss of the proposed waveguide is as small as similar to 1/10, compared with that of a conventional waveguide under the conditions of broadband bandwidth (>20 GHz) for both the loss and dispersion, due to the broadband low-dispersion below the light line of air, at which low-loss conditions are satisfied. Finally, we demonstrate 36 Gbit s(-1) error-free THz communications using the isosceles triangular lattice photonic-crystal waveguide. (C) 2019 The Japan Society of Applied Physics