Inhomogeneous lossy waveguide mode analysis

This paper discusses electromagnetic numerical mode analysis in waveguides with materially inhomogeneous cross-sections and material dissipation. A full-wave formulation of Maxwell's homogeneous equations including Gauss electric law, stable at vanishing propagation constant is implemented and verified in terms of the hp-adaptive version of the finite element method. It provides the possibility to use high order polynomial enrichments combined with strongly graded meshes. It is considered most efficient in resolving the loss of solution regularity at material interfaces with large contrast. Numerical examples including materially lossless homogeneous and inhomogeneous cross sections with and without losses are analysed to corroborate the implementation. The efficiency of using higher order polynomial enrichments is shown. The approach is anticipated to have a broad application, from modern on-chip interconnect and antenna technologies to the design of low observable aerial vehicles.