Open AccessDiscrete dipole approximation for magneto-optical scattering calculations
Author(s) -
Damon A. Smith,
Kevin L. Stokes
Publication year - 2006
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.14.005746
Subject(s) - faraday effect , discrete dipole approximation , scattering , physics , optics , light scattering , mie scattering , faraday rotator , magnetic nanoparticles , magnetic dipole , dipole , condensed matter physics , materials science , computational physics , molecular physics , nanoparticle , magnetic field , quantum mechanics
Magneto-optical spectra (Faraday effect) for nanometer-scale particles and collections of particles are calculated using a modification of the discrete dipole approximation (DDA). The approximation is used as a finite-element method for non-spherical particles whose dimensions are on the order of or smaller than the incident light wavelength, lambda. Also, we use the approximation to calculate scattering from arrangements of spherical nanoparticles with diameters << lambda. We propose that for scattering from subwavelength magnetic particles, the specific Faraday rotation should be defined as the difference in optical extinction for left- and right-circularly polarized light. We apply the model to calculations of Faraday rotation from magnetite nanowires as well as a binary (two-component) nanoparticle arrangement. Enhancements in Faraday rotation are predicted for composites containing both noble metal and ferrite nanoparticles.