Design and Analysis of a Trident-Shaped 1x3 Dielectric Waveguide Splitter for THz Applications

This scientific paper is an outcome of the MARIE project (for more information, see trrmarie.de) C12. We investigate a 1x3 splitting structure based on a dielectric slot waveguide (DSWG) in high resistivity float-zone silicon (HR-Si). The power is distributed from the bus towards the branches via coupling of the evanescent field. The additional paths allow the introduction of liquids for sensing applications. The splitting process is studied by Beam Propagation Method (BPM) for the initial investigation of the behavior and a broadband optimization. Further investigations were additionally verified via finite element method (FEM). The chips are fabricated through a new double-sided etching process. The splitter was characterized using a 2D field scanning system utilizing a 2-Port Vectorial Network Analyzer (VNA) including two extension modules in the 260 to 400 GHz domain. The measurement results show a transmission of -6 dB for the bus while both arms exhibited -10 dB each.