The Effect of Humidity and Temperature on Dielectric Fibre–Bound THz Transmission

Abstract

We experimentally study the impact of humidity and temperature on the transmission of 120-GHz waves through a solid core fibre of polypropylene without cladding. We find that the transmission is greatly affected by both, an increase in the water vapour density and in the temperature. We attribute this to the growth of a water film around the fibre which attenuates the evanescent field, and to an increasing absorption of the material with increasing temperature.