Frequency-dependent characterization of THz Sommerfeld wave propagation on single-wires.

In this work, measurements and numerical field simulations highlighting the characteristic propagation behavior of THz surface-wave pulses along bare and dielectrically coated metal wires are presented. An optoelectronic time-domain measurement setup with a freely-positionable probe-tip is used for detection of electrical field transients after different propagation lengths along the wires. Frequency-dependent attenuation and dispersion parameters are determined in the range of 0.02 THz to 0.4 THz. Our results are in good agreement with numerical field simulations considering the propagation of an axial Sommerfeld surface-wave with metallic and dielectric losses. We discuss the influence of wire radius on wave propagation behavior and the application of THz single-wires for sensing.