Discrete dipole moment method for calculation of the T matrix for nonspherical particles
Abstract
A computational method, based on a moment solution to the discrete dipole approximation (DDA) interaction equations, is proposed for calculation of the T matrix of arbitraryshaped particles. It is shown that the method will automatically provide the conservationofenergy and origininvariance properties required of the T matrix. Furthermore, the method is significantly faster than a Tmatrix calculation by direct inversion of the DDA equations. Because the method retains the dipole lattice representation of the particle, it can be applied with relative ease to particles with irregular shapesalthough in the same respect it will not automatically simplify for axisymmetric particles. Calculations of scattering matrix distributions, in fixed and random orientations, are made for tetrahedron, cylindrical, and prolate spheroid particle shapes and compared with DDA and extended boundary condition method results.
 Publication:

Journal of the Optical Society of America A
 Pub Date:
 May 2002
 DOI:
 10.1364/JOSAA.19.000881
 Bibcode:
 2002JOSAA..19..881M
 Keywords:

 electromagnetic wave scattering;
 matrix algebra;
 boundaryvalue problems;
 invariance;
 approximation theory;
 method of moments