THz Multimode Interference Power Divider Based on Groove Gap Waveguide Configuration

This article proposes a groove gap waveguide (GGW) for terahertz (THz) applications. At first, a metal unit cell is introduced, which shows a bandgap frequency range of 1-2 THz. The metal pins are surrounded by benzocyclobutene (BCB) polymer to facilitate the fabrication process. The GGW with a width of 133.40 μm has a cutoff frequency of 1.2 THz. A multimode interference (MMI) power divider is also investigated using the proposed structure in the frequency range of 1.3 to 1.8 THz. The S-parameters and electromagnetic power distributions were determined for a 1 × 2 MMI-power divider with a width of 351.52 μm and length of 103.40 μm. Meanwhile, the effect of length and width variations of the MMI-power divider on the S-parameters is studied. This novel 3 dB MMI structure can be used in a variety of terahertz applications.