Fabrication of bendable low-loss terahertz hollow waveguides based on plastic tubes

With the rapid development of terahertz (THz) science and technology, THz transmission has attracted widespread attention. Compared with wireless transmission in free space, THz wave can achieve bending, low-loss and stable propagation in the waveguide. Several types of THz waveguides have been reported. Among them, THz hollow waveguide (HWG) possesses the advantages such as simple structure, easy preparation and low cost. Recently, bendable and low-loss plastic THz HWGs has made progress in our group. This paper gives a review of the research progress in the field of the THz HWGs based on plastic tubing materials, including polymer tube waveguide, metal-coated polymer HWG and metal/dielectric polymer HWG. Problems existing in the plastic HWGs and key points of future research work were discussed with consideration of some issues aroused in practical applications.