78355 20201019094020.0 doi 10.1088/1361-6463/aab05f sideral 105470 ART-2018-105470 eng (orcid)0000-0002-2464-5626 Sanz-Felipe, Á. Universidad de Zaragoza Analysis of the optical transmission of a ferrofluid by an electromagnetic mixture law 2018 Access copy available to the general public Unrestricted Evolution of the optical transmission of a ferrofluid after magnetic field commutation is analyzed by means of an approach based on the so-called mixture laws: expressions which predict the effective permittivity of heterogeneous media as a function of their constituents' permittivities, their proportions and the way they are arranged. In particular, this work is based on a law proposed by Sihvola and Kong for the effective permittivity of a host substance with ellipsoidal inclusions. Ferrofluids are peculiar examples of this kind of media: with the solvent as host, the inclusions are nanoparticle agglomerates whose shapes become modified by magnetic field exposure. In this work, experimental optical transmission of a ferrofluid is compared with predictions based on Sihvola and Kong''s law. A remarkable coincidence is obtained both in the absence of magnetic field, without using any fitting parameter, and in the presence of magnetic field, employing the inclusions' average ellipticity as the fitting parameter. The results obtained for time dependent optical transmission of a ferrofluid after magnetic field switch on or off allow one to estimate how the average shape of the agglomerates evolves over time. On the other hand, mixture laws are proven to be an interesting alternative to scattering concepts to model the optical transmission changes experienced by ferrofluids once they are exposed to magnetic fields. info:eu-repo/grantAgreement/ES/MINECO/TEC2014-52642-C2-2-R info:eu-repo/grantAgreement/ES/UZ/UZ2017-CIE-07 info:eu-repo/semantics/openAccess All rights reserved http://www.europeana.eu/rights/rr-f/ 2.829 2018 PHYSICS, APPLIED 45 / 148 = 0.304 2018 Q2 T1 0.805 2018 Acoustics and Ultrasonics 2018 Q1 Surfaces, Coatings and Films 2018 Q1 Electronic, Optical and Magnetic Materials 2018 Q1 Condensed Matter Physics 2018 Q1 info:eu-repo/semantics/article info:eu-repo/semantics/acceptedVersion (orcid)0000-0002-8738-753X Martín, J.C. Universidad de Zaragoza 2002 247 Universidad de Zaragoza Dpto. Física Aplicada Área Electromagnetismo 2002 647 Universidad de Zaragoza Dpto. Física Aplicada Área Óptica 51, 13 (2018), 135001 [6 pp] J. phys., D. Appl. phys. JOURNAL OF PHYSICS D-APPLIED PHYSICS 0022-3727 320720 http://zaguan.unizar.es/record/78355/files/texto_completo.pdf Postprint 56654 http://zaguan.unizar.es/record/78355/files/texto_completo.jpg?subformat=icon icon Postprint oai:zaguan.unizar.es:78355 articulos driver 2020-10-19-09:35:38 ARTICLE