Discretization error due to the identity operator in surface integral equations

We consider the accuracy of surface integral equations for the solution of scattering and radiation problems in electromagnetics. In numerical solutions, second-kind integral equations involving well-tested identity operators are preferable for efficiency, because they produce diagonally-dominant matrix equations that can be solved easily with iterative methods. However, the existence of the well-tested identity operators leads to inaccurate results, especially when the equations are discretized with low-order basis functions, such as the Rao-Wilton-Glisson functions. By performing a computational experiment based on the nonradiating property of the tangential incident fields on arbitrary surfaces, we show that the discretization error of the identity operator is a major error source that contaminates the accuracy of the second-kind integral equations significantly.


Symplectic and multi-symplectic methods for coupled nonlinear Schrodinger equations with periodic solutions
Aydin, A.; Karasoezen, B. (Elsevier BV, 2007-10-01)
We consider for the integration of coupled nonlinear Schrodinger equations with periodic plane wave solutions a splitting method from the class of symplectic integrators and the multi-symplectic six-point scheme which is equivalent to the Preissman scheme. The numerical experiments show that both methods preserve very well the mass, energy and momentum in long-time evolution. The local errors in the energy are computed according to the discretizations in time and space for both methods. Due to its local nat...
Energy states of the Hulthen plus Coulomb-like potential with position-dependent mass function in external magnetic fields
Eshghi, M.; Sever, Ramazan; Ikhdair, S. M. (IOP Publishing, 2018-02-01)
We need to solve a suitable exponential form of the position-dependent mass (PDM) Schrodinger equation with a charged particle placed in the Hulthen plus Coulomb-like potential field and under the actions of the external magnetic and Aharonov-Bohm (AB) flux fields. The bound state energies and their corresponding wave functions are calculated for the spatially-dependent mass distribution function of interest in physics. A few plots of some numerical results with respect to the energy are shown.
Analytical Solutions to the Klein-Gordon Equation with Position-Dependent Mass for q-Parameter Poschl-Teller Potential
Arda, Altug; Sever, Ramazan; TEZCAN, CEVDET (IOP Publishing, 2010-01-01)
The energy eigenvalues and the corresponding eigenfunctions of the one-dimensional Klein-Gordon equation with q-parameter Poschl-Teller potential are analytically obtained within the position-dependent mass formalism. The parametric generalization of the Nikiforov-Uvarov method is used in the calculations by choosing a mass distribution.
Approximate solution to the time-dependent Kratzer plus screened Coulomb potential in the Feinberg-Horodecki equation
Farout, Mahmoud; Sever, Ramazan; Ikhdair, Sameer M. (IOP Publishing, 2020-06-01)
We obtain the quantized momentum eigenvalues P-n together with space-like coherent eigenstates for the space-like counterpart of the Schrodinger equation, the Feinberg-Horodecki equation, with a combined Kratzer potential plus screened coulomb potential which is constructed by temporal counterpart of the spatial form of these potentials. The present work is illustrated with two special cases of the general form: the time-dependent modified Kratzer potential and the time-dependent screened Coulomb potential.
Exact solution of the Dirac equation with the Mie-type potential under the pseudospin and spin symmetry limit
Aydogdu, Oktay; Sever, Ramazan (Elsevier BV, 2010-02-01)
We investigate the exact solution of the Dirac equation for the Mie-type potentials under the conditions of pseudospin and spin symmetry limits. The bound state energy equations and the corresponding two-component spinor wave functions of the Dirac particles for the Mie-type potentials with pseudospin and spin symmetry are obtained. We use the asymptotic iteration method in the calculations. Closed forms of the energy eigenvalues are obtained for any spin-orbit coupling term K. We also investigate the energ...
Citation Formats
Ö. S. Ergül, “Discretization error due to the identity operator in surface integral equations,” COMPUTER PHYSICS COMMUNICATIONS, pp. 1746–1752, 2009, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/37755.