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

Valagiannopoulos, CA; Tsitsas, NL

dc.contributor.author	Valagiannopoulos, CA	en
dc.contributor.author	Tsitsas, NL	en
dc.date.accessioned	2014-03-01T01:31:00Z
dc.date.available	2014-03-01T01:31:00Z
dc.date.issued	2009	en
dc.identifier.issn	1084-7529	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/19711
dc.subject.classification	Optics	en
dc.subject.other	Average values	en
dc.subject.other	Environmental science	en
dc.subject.other	Far-field patterns	en
dc.subject.other	Linear combinations	en
dc.subject.other	Numerical results	en
dc.subject.other	Piece wise	en
dc.subject.other	Plane-wave scatterings	en
dc.subject.other	Scattered fields	en
dc.subject.other	Step approximations	en
dc.subject.other	T matrixes	en
dc.subject.other	T-matrix methods	en
dc.subject.other	Taylor expansions	en
dc.subject.other	Wave numbers	en
dc.subject.other	Chemical engineering	en
dc.subject.other	Plasmons	en
dc.subject.other	Electromagnetic wave scattering	en
dc.title	Linearization of the T-matrix solution for quasi-homogeneous scatterers	en
heal.type	journalArticle	en
heal.identifier.primary	10.1364/JOSAA.26.000870	en
heal.identifier.secondary	http://dx.doi.org/10.1364/JOSAA.26.000870	en
heal.language	English	en
heal.publicationDate	2009	en
heal.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 (k) over bar. 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 (k) over bar. 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 wave- number's deviations from (k) over bar. 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. (C) 2009 Optical Society of America	en
heal.publisher	OPTICAL SOC AMER	en
heal.journalName	Journal of the Optical Society of America A: Optics and Image Science, and Vision	en
dc.identifier.doi	10.1364/JOSAA.26.000870	en
dc.identifier.isi	ISI:000265446900017	en
dc.identifier.volume	26	en
dc.identifier.issue	4	en
dc.identifier.spage	870	en
dc.identifier.epage	881	en