Liquid Crystal Coaxial Phase Shifter Designs at 0.3 THz

This work proposes two designs of liquid crystal (LC)-filled coaxial transmission line phase shifters evaluated at 0.3 terahertz (THz). The classic coaxial topology is robust to environmental noise, whereas it is susceptible to higher-order modes from millimetre-wave towards THz wavelengths, which impedes the low-insertion-loss phase-shifting functionality. By suppressing the first higher-order TE11 mode with a 25% bandwidth allowance, the figure-of-merit of the two designs reports 35.13°/dB and 34.82°/dB. The results from this analytical and finite-element analysis shape the direction and feasibility of the THz coaxial phase shifting technology with LC actioned as tunable dielectrics.