Amplitude and phase of light scattered by micro-scale aggregates of dielectric spheres: Comparison between theory and microwave analogy experiments

• Published in: Journal of quantitative spectroscopy & radiative transfer Vol. 103; no. 1; pp. 156 - 167
• Main Authors: Sabouroux, Pierre, Stout, Brian, Michel Geffrin, Jean, Eyraud, Christelle, Ayranci, Isil, Vaillon, Rodolphe, Selçuk, Nevin
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 2007; Elsevier
• Subjects: Aggregate; DDA method; Dielectric sphere; Electromagnetism; Engineering Sciences; Mechanics; Microwave; Microwave analogy; Optics; Photonic; Physics; Scattering; T-matrix method; Thermics; T-matrix method; Scattering; Microwave; DDA method; Microwave analogy; Aggregate; Dielectric sphere
• ISSN: 0022-4073; 1879-1352
• DOI: 10.1016/j.jqsrt.2006.06.001

Light scattering is a useful diagnostic tool for characterization of particles. Direct scattering measurements for arbitrarily shaped micro-scale particles is difficult due to small-scale limitations. Microwave analogy is a convenient approach to realize such measurements as it enables realization of analogous experiments with larger model particles in a spectral domain where wavelengths are on centimeter scale. In the present study a test model analogous to light scattering by a micro-scale aggregate of dielectric spheres was constructed and experimentally characterized in the microwave regime. Measured amplitude and phase of the scattered field were compared with theoretical predictions obtained from quasi-exact multiple-scattering T-matrix method and discrete dipole approximation (DDA). Excellent agreement demonstrates the validities of both the experiment and the models.