A variational digitized Green function approach to light scattering by small particles.

摘要

The variational Green function (VGF) algorithm and the underlying theory are presented. This coupled dipole algorithm models homogeneous dielectric particles of arbitrary shape by subdividing the particle into small cells. Computation is achieved without the huge matrix inversion and storage required by standard coupled dipole methods. Instead, a variational technique is used to find the coeffcients of the internal field in a plane wave expansion. Predictions of differential cross sections are compared with predictions from Mie, T-matrix, and DGF calculations for homogeneous spheres, spheroids, and cubes. Convergence tests are presented for the VGF calculations as the number of plane wave terms is increased. Storage requirements and computation time are discussed. Applications and future studies are suggested.