RT journal article
T1 Magneto-Optic Faraday Effect in Maghemite Nanoparticles/Silica Matrix Nanocomposites prepared by the Sol-Gel Method
A1 Domínguez, Manuel
A1 Ortega, Daniel
A1 Garitaonandía, J.S.
A1 Litrán Ramos, Rocío
A1 Barrera-Solano, M. Carmen
A1 Blanco, Eduardo
A1 Ramírez del Solar, Milagrosa
K1 Nanocomposite
K1 Magnetic nanoparticles
K1 Magneto-optical properties
AB Bulk monolithic samples of γ-Fe2O3/SiO2 composites with different iron oxide/silica ratios have been prepared by the sol-gel technique. Iron oxide nanoparticles are obtained in-situ during heat treatment of samples and silica matrix consolidation. Preparation method was previously optimized to minimize the percentage of antiferromagnetic α-Fe2O3 and parallelepipeds of roughly 2×5×12 mm, with good mechanical stability, are obtained. RT magnetization curves show a non-histeretic behavior. Thus, magnetization measurements have been well fitted to an expression that combines the Langevin equation with an additional linear term, indicating that some of the nanoparticles are still superparamagnetic as confirmed by X-Ray Diffraction and Electron Microscopy measurements. ZFC/FC experiments show curves with slightly different shapes, depending on the size and shape distribution of nanoparticles for a given composition. Magneto-optical Faraday effect measurements show that the Faraday rotation is proportional to magnetization of the samples, as expected. As a demonstration of their sensing possibilities, the relative intensity of polarized light, measured at 5º from the extinction angle, was plotted versus applied magnetic field.
YR 2008
FD 2008-10
LK http://hdl.handle.net/10498/7374
UL http://hdl.handle.net/10498/7374
LA eng
NO Published in Journal of Magnetism & Magnetic Materials an Elsevier Pub.
DS Repositorio Institucional de la Universidad de Cádiz
RD 21-sep-2026