Linearization of the T-matrix solution for quasi-homogeneous scatterers

Constantine A. Valagiannopoulos, Nikolaos L. Tsitsas

Research output: Contribution to journalArticlepeer-review

14 Citations (Scopus)

Abstract

Interesting applications arising in optical and chemical engineering, environmental science, and biology motivate the investigation of electromagnetic wave scattering problems by radially inhomogeneous obstacles. Our main purpose is the investigation of plane-wave scattering by quasi-homogeneous obstacles, that is, obstacles with wavenumbers not exhibiting large variations from a specific average value k̄. The analysis is presented separately for a slab (1D), a cylindrical (2D), and a spherical (3D) scatterer. First, we consider a step approximation of the wavenumber and express the field coefficients by applying a T-matrix method for the corresponding piecewise homogeneous scatterer. Then, by performing an appropriate Taylor expansion, we express the field coefficients as linear combinations of the distances of the wavenumber samples from k̄. The combinations' weights are called layer-factors, because each one describes the contribution of a specific layer in the scattered field. Furthermore, it is shown that the far-field pattern of the quasi-homogeneous scatterer is decomposed into that of the respective homogeneous scatterer plus the perturbation far-field pattern, depending on the wavenumber's deviations from k̄. Several numerical results are presented concerning the comparison of the far-field patterns computed by the proposed technique and the T-matrix method, as well as investigations of the perturbation far-field pattern and the layer-factors. Linear, sinusoidal, Lunenburg type, and triangular wavenumber profiles are analyzed.

Original languageEnglish
Pages (from-to)870-881
Number of pages12
JournalJournal of the Optical Society of America A: Optics and Image Science, and Vision
Volume26
Issue number4
DOIs
Publication statusPublished - Apr 1 2009

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Atomic and Molecular Physics, and Optics
  • Computer Vision and Pattern Recognition

Fingerprint Dive into the research topics of 'Linearization of the T-matrix solution for quasi-homogeneous scatterers'. Together they form a unique fingerprint.

Cite this