A novel low-loss Terahertz waveguide: Polymer tube

We propose a kind of novel low-loss Terahertz (THz) waveguide, a polymer tube with a cross section of ring structure. Low-loss property of the polymer tube for THz guiding is achieved due to the effect of the air core inside the polymer tube which traps a large part of mode power and, at the same time, enlarges the mode area of the fundamental mode. Both the polymer tube and a solid polymer fiber are comparatively investigated, considering effective indexes, mode area, power fraction, relative absorption loss and mode profile. Simulation results show that the proposed polymer tube exhibits better loss property and confinement property than the solid polymer fiber. As an example, we finally show the experimentally measured property of a Polytetrafluoroethylene (PTFE) tube. (C)2010 Optical Society of America