Scattering of electromagnetic radiation by a multilayered sphere

Abstract

The computer implementation of the algorithm for the calculation of electromagnetic radiation scattering by a multilayered sphere developed by Yang, is presented. It has been shown that the program is effective, resulting in very accurate values of scattering efficiencies for a wide range of size parameters, which is a considerable improvement over previous implementations of similar algorithms. The program, named scattnlay, would be the first of its kind to be publicly available. Program summaryProgram title: scattnlayCatalogue identifier: AEEY_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEEY_1_0.htmlProgram obtainable from: CPC Program Library, Queen's University, Belfast, N. IrelandLicensing provisions: Gnu General Public License (GPL)No. of lines in distributed program, including test data, etc.: 8932No. of bytes in distributed program, including test data, etc.: 175 276Distribution format: tar.gzProgramming language: ANSI CComputer: Any with a C compilerOperating system: Linux (any), Windows, SolarisRAM: ∼1–100 MBClassification: 1.3Nature of problem: The scattering of electromagnetic (EM) radiation by a multilayered sphere is an interesting phenomenon to study for the application of such materials in several fields. Just to mention two examples, metal nanoshells (a dielectric core surrounded by a metallic shell) are a class of nanoparticles with tunable optical resonances that can be used, among others, in medicine for optical imaging and photothermal cancer therapy; while in the field of atmospheric sciences, light absorption by aerosols has a heating effect in the atmosphere that is of great interest to study several climatic effects. Although at first glance the expressions of the scattering coefficients seem simple and straightforward to implement, they involve several numerical difficulties which make most of the existent algorithms inapplicable to several extreme cases. More recently, Yang [1] has developed an improved recursive algorithm that circumvents most of the numerical problems present in previous algorithms, which is implemented in the current program.Solution method: Calculations of Mie scattering coefficients and efficiency factors for a multilayered sphere as described by Yang [1], combined with standard solutions of the scattering amplitude functions.Restrictions: Single scattering, permeability of the layers is always unity.Running time: Seconds to minutes