“…Within this class of materials, our work is devoted to c-Fe 2 O 3 -SiO 2 NC's with application in magneto-optical sensors. Taking into account the followed preparation method and previously reported results for other particulate systems [2], a superparamagnetic behavior would be expected; however, a predominant blocked state combined with features associated with superparamagnetic NP's is the resulting behavior, as seen in previous Mössbauer, FMR and ZFC/FC measurements [3,4]. The present work is aimed to provide a model of the NP growth and explaining the observed macroscopic magnetic properties.…”