Abstract

In this paper we have analyzed circumstances under which a rigid particulate sample can behave optically as a true discrete random medium consisting of particles randomly moving relative to each other during measurement. To this end, we applied the numerically exact superposition $T$-matrix method to model far-field scattering characteristics of fully ordered and quasi-randomly arranged rigid multiparticle groups in fixed and random orientations. We have shown that, in and of itself, averaging optical observables over movements of a rigid sample as a whole is insufficient unless it is combined with a quasi-random arrangement of the constituent particles in the sample. Otherwise, certain scattering effects typical of discrete random media (including some manifestations of coherent backscattering) may not be accurately replicated.

© 2016 Optical Society of America

Demonstration of numerical equivalence of ensemble and spectral averaging in electromagnetic scattering by random particulate media

Michael I. Mishchenko, Janna M. Dlugach, and Nadezhda T. Zakharova
J. Opt. Soc. Am. A 33(4) 618-624 (2016)

Multiple scattering by random particulate media: exact 3D results

Michael I. Mishchenko, Li Liu, Daniel W. Mackowski, Brian Cairns, and Gorden Videen
Opt. Express 15(6) 2822-2836 (2007)

Electromagnetic scattering by densely packed particulate ice at radar wavelengths: exact theoretical results and remote-sensing implications

Michael I. Mishchenko and Li Liu
Appl. Opt. 48(13) 2421-2426 (2009)

Effects of absorption on multiple scattering by random particulate media: exact results

Michael I. Mishchenko, Li Liu, and Joop W. Hovenier
Opt. Express 15(20) 13182-13187 (2007)

Equivalence theorem for light waves on scattering from particulate media

Hao Wu, Xiaoning Pan, Xiaoling Ji, Daomu Zhao, and Tao Wang
J. Opt. Soc. Am. A 33(10) 2077-2080 (2016)