THz Filter Using the Transverse-electric (TE₁) Mode of the Parallel-plate Waveguide

Abstract

The results of the experimental and theoretical studies conducted on terahertz filtering using two parallel-plate waveguides (PPWGs) are presented herein. The first PPWG with 355 μm plate separation generates 4 THz bandwidth TM modes (TM0, TM2, and TM4), whereas the second PPWG with 100 μm plate separation operated the THz filter for the generated TM modes with 1.5 THz cutoff frequency. The outgoing THz wave of the two PPWGs was truncated until 1.5 THz, and the system was operated using a high-pass THz filter. The absorption and dispersion of the combined TM and TE modes for the filtering system were calculated. The theoretical calculation and measurement results for the cutoff and oscillation frequency in the spectrum domain agreed well.