Integrating rotationally-symmetric 2D-FEM into a dedicated rotationally-symmetric Mode-Matching for waveguide devices

There are many tools for the study of waveguide devices. The two-dimensional Finite Element Method is one of the most relevant ones when the objective is performing modal analysis, and Mode-Matching is widely used when analysing discontinuities in terms of modes. Due to the synergies between both methods, it is very interesting to study their combination in special cases commonly appearing in the literature, such as the problem of discrete rotationally-symmetric waveguides. In this work we present how the integration of the 2D Finite Element Method for Mode-Matching with rotationally symmetric modes must be done, so that it may employed to perform a more efficient and accurate analysis of devices composed of waveguide discontinuities.