Calculation of a parallel-plate waveguide with a chiral insert by the mixed finite element method

A parallel-plate waveguide with metallic boundaries, containing an insert of a chiral substance, is considered. The field distribution inside the insert is studied when the system is excited by the guide’s normal wave incident on the insert. The problem is considered in the full vector formulation. The waveguide is calculated by the mixed finite element method, which makes it possible to avoid spurious modes (so-called spirits).