“…That is why there are no pure TE or TM modes in spheroids but only hybrid ones. Different methods of separation of variables (SVM) using series expansions with either spheroidal or spherical functions have been proposed [11], [12], [13]. Unfortunately they lead to extremely bulky infinite sets of equations which can be solved numerically only in simplest cases and the convergence is not proved.…”
Abstract-Using quasiclassical approach rather precise analytical approximations for the eigenfrequencies of whispering gallery modes in convex axisymmetric bodies may be found. We use the eikonal method to analyze the limits of precision of quasiclassical approximation using as a practical example spheroidal dielectric cavity. The series obtained for the calculation of eigenfrequencies is compared with the known series for dielectric sphere and with numerical calculations. We show how geometrical interpretation allows expansion of the method on arbitrary shaped axisymmetric bodies.
“…That is why there are no pure TE or TM modes in spheroids but only hybrid ones. Different methods of separation of variables (SVM) using series expansions with either spheroidal or spherical functions have been proposed [11], [12], [13]. Unfortunately they lead to extremely bulky infinite sets of equations which can be solved numerically only in simplest cases and the convergence is not proved.…”
Abstract-Using quasiclassical approach rather precise analytical approximations for the eigenfrequencies of whispering gallery modes in convex axisymmetric bodies may be found. We use the eikonal method to analyze the limits of precision of quasiclassical approximation using as a practical example spheroidal dielectric cavity. The series obtained for the calculation of eigenfrequencies is compared with the known series for dielectric sphere and with numerical calculations. We show how geometrical interpretation allows expansion of the method on arbitrary shaped axisymmetric bodies.
“…Thus, it can model much better than the spherical geometry, a large variety of inclusions or inhomogeneities participating in scattering processes. [1][2][3][4][5] A lot of effort has been devoted to study the direct scattering problem by obstacles [6][7][8][9][10][11][12][13] and especially from spheroids both theoretically and numerically. The adopted methodology in each case depends crucially on the frequency (wavenumber) range under consideration.…”
A complete set of radiating “outwards” eigensolutions of the Helmholtz equation, obtained by transforming appropriately through the Vekua mapping the kernel of Laplace equation, is applied to the investigation of the acoustic scattering by penetrable prolate spheroidal scatterers. The scattered field is expanded in terms of the aforementioned set, detouring so the standard spheroidal wave functions along with their inherent numerical deficiencies. The coefficients of the expansion are provided by the solution of linear systems, the conditioning of which calls for arbitrary precision arithmetic. Its integration enables the polyparametric investigation of the convergence of the current approach to the solution of the direct scattering problem. Finally, far‐field pattern visualization in the 3D space clarifies the preferred scattering directions for several frequencies of the incident wave, ranging from the “low” to the “resonance” region.
“…Different methods of separation of variables (SVM) using series expansions with either spheroidal or spherical functions have been proposed. [11][12][13] Unfortunately they lead to extremely bulky infinite sets of equations which can be solved numerically only in simplest cases and the convergence is not proved. Exact characteristic equation for the eigenfrequencies in dielectric spheroid was suggested 14 without provement that if real could significantly ease the task of finding eigenfrequencies.…”
Using quasiclassical approach rather precise analytical approximations for the eigenfrequencies of whispering gallery modes in convex axisymmetric bodies may be found. We use the eikonal method to analyze the limits of precision of this approach using as a practical example spheroidal dielectric cavity. The series obtained for the calculation of eigenfrequency is compared with the known series for dielectric sphere and numerical calculations.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.