Quasimode computation in structures including several dispersive materials

摘要

We present a new method for the direct computation of the resonances associated with electromagnetic structures including media with highly dispersive permittivities. The FEM discretization of this problem leads to a generalized polynomial eigenvalue problem (PEP). We have developped a very general method to compute such modes and to limit the order of the PEP when the structure involves several dispersive media. As the accurate description of the dispersive permittivity in the form of a rational function of pulsation is a critical point in our method, we also describe a very general procedure to obtain a causal fit o f t he p ermittivity o f materials from experimental data with very few parameters. Unlike other closed forms proposed in the literature, the particularity of this approach lies in its independence towards the material or frequency range at stake.