Demonstration of a planar multimodal periodic filter at THz frequencies

TL;DR

This paper demonstrates a novel planar multimodal periodic filter operating at THz frequencies, combining theory, design, simulation, and experimental validation for a band-stop filter centered at 0.8 THz.

Contribution

It introduces a new multimodal filter design using coplanar structures for THz applications, enabling flexible and potentially active control of filter properties.

Findings

Good agreement between theory, simulation, and experiment.

Achieved a band-stop filter at 0.8 THz with 0.07 THz bandwidth.

Demonstrated feasibility of multimodal periodic filters at THz frequencies.

Abstract

This paper presents a planar multimodal periodic filter that is constructed from alternating sections of coplanar stripline and the odd-mode of a finite-ground plane coplanar waveguide constructed on a 1 um silicon nitride substrate to facilitate operation at THz frequencies. The multimode configuration differs from standard single-mode periodic filters and enables flexible designs and the possibility for active control of the filter characteristics. For this proof-of-concept, we present the relevant theory and design procedures required to develop a band-stop filter that has a center frequency of fc = 0.8 THz and a bandwidth of df = 0.07 THz. We find good agreement between theory, simulation, and experiment.