Magnetic Properties of Small Magnetite Nanocrystals

MUSCAS, GIUSEPPE;CONCAS, GIORGIO;CANNAS, CARLA;MUSINU, ANNA MARIA GIOVANNA;ARDU, ANDREA;Orrù F;Fiorani D;Laureti S;Rinaldi G;PEDDIS, DAVIDE;Peddis D.

2013-01-01

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Abstract

This paper focuses on the study of the magnetic properties of 9 nm magnetite nanocrystals. XRD and TEM measurements indicate the presence of crystalline particles, with a fraction of them only partially crystallized or highly defective. The analysis of the temperature dependence of the zero-field-cooled/field-cooled magnetization and of the thermoremanent magnetization provides evidence of the existence of three magnetic regimes: a high temperature regime (300-100 K), an intermediate regime (100-20 K), and a low temperature regime (below 20 K). The characteristics of such regimes are discussed