Broadband THz guidance in helical waveguides

We experimentally observe broadband Terahertz pulse propagation in flexible metal helix waveguides. Our measurements are in very good agreement with finite-difference time domain simulations. The waveguides have a constant attenuation coefficient of 0.2 cm^-1 in the region between 0.3 and 0.9 THz. The measured temporal signals indicate that the THz pulse is confined to the core of the helical waveguide. Moreover, a constant magnitude of the group-velocity dispersion parameter of less than 1 ps THz^-1 cm^-1 in the region from 0.5 THz to 0.9 THz reveals the low dispersive behavior of the helical waveguide.