Static and dynamical magnetic properties of Fe nanoparticles (NPs) embedded in non-magnetic (Ag) and antiferromagnetic (Cr) matrices with a volume filling fraction (VFF) of 10% have been investigated. In both Fe@Ag and Fe@Cr nanocomposites, the Fe NPs have a narrow size distribution, with a mean particle diameter around 2 nm. In both samples, the saturation magnetization reaches that of Fe bulk bcc, suggesting the absence of alloying with the matrices. The coercivity at 5 K is much larger in Fe@Cr than in Fe@Ag as a result of the strong interaction between the Fe NPs and the Cr matrix. Temperature-dependent magnetization and ac-susceptibility measurements point out further evidence of the enhanced interparticle interaction in the Fe@Cr system. While the behaviour of Fe@Ag indicates the presence of weakly interacting magnetic monodomain particles with a wide distribution of blocking temperatures, Fe@Cr behaves like a superspin glass produced by the magnetic interactions between NPs.
|Titolo:||Magnetic anisotropy and magnetization dynamics of Fe nanoparticles embedded in Cr and Ag matrices|
|Data di pubblicazione:||2015|
|Appare nelle tipologie:||01.01 - Articolo su rivista|
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|Peddis et al. - 2015 - Magnetic anisotropy and magnetization dynamics of Fe nanoparticles embedded in Cr and Ag matrices.pdf||Documento in versione editoriale||Administrator Richiedi una copia|
|Peddis et al. - 2015 - Magnetic anisotropy and magnetization dynamics of Fe nanoparticles embedded in Cr and Ag matrices(2).pdf||Supporting Information||Altro materiale allegato||Administrator Richiedi una copia|