Beschreibung:
The rapid development of terahertz (THz) technology makes the study of terahertz waveguide indispensable. In the current research on terahertz waveguides, there is still a lack of flexible waveguides for stable transmission in hot/cold environments. In this work, a mechanically strong and high-and low-temperature resistant PEEK (polyether ether ketone) tube was selected as the structural tube. On the basis of plasma treatment on the surface of PEEK tube, a high-performance silver (Ag) coated hollow THz waveguide was prepared. It was found that the plasma treatment can greatly improve the surface bonding strength between the PEEK tube and the silver film, which enhances the bending performance of the PEEK/Ag-coated hollow waveguide. The minimum bending radius of the 3-mm-bore waveguide can reach 3 cm without damaging the waveguide structure. Meanwhile, the good thermal properties of the PEEK tube and its good bonding with the silver layer allow the waveguide to transmit terahertz waves stably at high (150°C) and low (-78.5°C) temperatures with the no more than 5% fluctuation in output power. In addition, the PEEK/Ag-coated hollow waveguide has extremely low transmission loss compared to other terahertz waveguides. The straight transmission losses for 0.3 and 0.1 THz wave of a 4.25-mm-bore PEEK/Ag-coated hollow waveguide is 0.67 and 1.26 dB/m at room temperature (25 °C). When the bending angle of the 4.25-mm-bore waveguide increases from 0 to 180 degrees, the transmission loss increases to 1.02 dB/m at 0.3 THz