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Efficient iterative solution of the discrete dipole approximation for magnetodielectric scatterers
Patrick C Chaumet1, Adel Rahmani
1Institut Fresnel, UMR 6133, Université Paul Cézanne, Marseille, France. patrick.chaumet@fresnel.fr
Optics Letters
|April 3, 2009
Summary
The discrete dipole approximation (DDA) method struggles with magnetic materials. This study explores iterative solvers for nonsymmetric systems arising from light scattering by objects with electric and magnetic responses.
Area of Science:
- Computational electromagnetics
- Light scattering theory
- Materials science
Background:
- The discrete dipole approximation (DDA) is a standard method for simulating light scattering.
- DDA typically solves symmetric linear systems for nonmagnetic materials.
- Nonsymmetric systems arise when magnetic responses are included.
Purpose of the Study:
- To investigate light scattering by objects with electric and magnetic responses.
- To evaluate iterative solvers for nonsymmetric DDA systems.
- To address limitations of DDA for magnetic materials.
Main Methods:
- Formulation of the DDA for objects with electric and magnetic susceptibility.
- Implementation of iterative solvers for nonsymmetric linear systems.
- Analysis of solver efficiency and convergence for DDA.
Main Results:
- Nonsymmetric linear systems are inherent to DDA with magnetic responses.
- Common iterative solvers may fail or perform poorly on these systems.
- The efficiency of various solvers for nonsymmetric DDA was assessed.
Conclusions:
- Extending DDA to include magnetic properties requires addressing nonsymmetric systems.
- Careful selection of iterative solvers is crucial for accurate and efficient simulations.
- This work provides insights into handling magnetic light scattering with DDA.
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