Analysis of the Scattering from a Two Stacked Thin Resistive Disks Resonator by Means of the Helmholtz–Galerkin Regularizing Technique

Abstract

In this paper, the scattering of a plane wave from a lossy Fabry–Perót resonator, realized with two equiaxial thin resistive disks with the same radius, is analyzed by means of the generalization of the Helmholtz–Galerkin regularizing technique recently developed by the author. The disks are modelled as 2-D planar surfaces described in terms of generalized boundary conditions. Taking advantage of the revolution symmetry, the problem is equivalently formulated as a set of independent systems of 1-D equations in the vector Hankel transform domain for the cylindrical harmonics of the effective surface current densities. The Helmholtz decomposition of the unknowns, combined with a suitable choice of the expansion functions in a Galerkin scheme, lead to a fast-converging Fredholm second-kind matrix operator equation. Moreover, an analytical technique specifically devised to efficiently evaluate the integrals of the coefficient matrix is adopted. As shown in the numerical results section, near-field and far-field parameters are accurately and efficiently reconstructed even at the resonance frequencies of the natural modes, which are searched for the peaks of the total scattering cross-section and the absorption cross-section. Moreover, the proposed method drastically outperforms the general-purpose commercial software CST Microwave Studio in terms of both CPU time and memory occupation.

Terahertz-range plasmon and whispering gallery mode resonances in the plane wave scattering from thin microsize dielectric disk with graphene covers

“…In order to validate the GBC model, i.e. the replacement of a finite-thickness graphene-covered disk with its zero-thickness counterpart, in figure 4, the frequency dependence of ACS for such a model with εr=1 and μc=1 eV is compared, for normal incidence, with ACS of two stacked graphene disks, with distance τ between them and the same other parameters, analysed using the full-wave guaranteed-convergence method proposed in [38]. As can be clearly seen, the agreement is very good across the entire frequency range considered.…”

Wave Diffraction from a Bicone Conjoined with an Open-Ended Conical Cavity

“…This technique has also been applied to analyse open-ended cylindrical and spherical cavities [33][34][35]. Various directions of analytical regularization methods are developed in [36][37][38][39], and references therein.…”