Low-loss Modes In Hollow Metallic Terahertz Waveguides With Dielectric Coatings

摘要

Cylindrical hollow-core metallic waveguides with an inner coating of polystyrene (PS) deposited over silver have losses less than 1dB/m for terahertz waves propagating in the HE_(11) mode. The thickness of the PS film determines whether the hybrid HE_(11) mode or the transverse TE_(01) mode exhibits the lowest loss. The mode selection is confirmed by studying mode profiles and transmission losses at 2.5 THz in waveguides with the dielectric coating thickness ranging from 0 to the optimum value of approximately 10 μm.