Título
Zn-doping effect on the energy barrier to magnetization reversal in superparamagnetic nickel ferrite nanoparticles
Autor
JOSE TRINIDAD ELIZALDE GALINDO
Colaborador
LUIS EDMUNDO FUENTES COBAS (Colaborador)
JOSE ANDRES MATUTES AQUINO (Colaborador)
Nivel de Acceso
Acceso Abierto
Materias
Resumen o descripción
Measurements of ac-susceptibility and dc-magnetization
were carried out on samples of Ni1−xZnxFe2O4 nanoparticles
(x = 0, 0.25, 0.5, 0.75) with average diameters D ≈
7 nm. Values of the superparamagnetic blocking temperature
TB were obtained from the characteristic temperature behavior
of the imaginary susceptibility χimag. An Arrhenius-type
law, which accurately describes the relationship between the
observation time τobs and the blocking temperature, was used
to determine the effective energy barrier to magnetization reversal
Ueff. A Zn-content dependence of the energy barrier is
observed, where Ueff changes little for 0 ≤ x ≤ 0.25, it peaks
at x = 0.5, and decreases back upon further Zn-doping. The
large increase of Ueff at x = 0.5 is attributed to an enhanced
magnetic anisotropy induced by the crossover between two spatial
arrangements of spins in the A and B sub-lattices of the
ferrimagnetic inverse spinel.
Fecha de publicación
mayo de 2007
Tipo de publicación
Artículo
Versión de la publicación
Versión enviada
Recurso de información
Formato
application/pdf
Idioma
Inglés
Repositorio Orígen
Fuente de Objetos Científicos Open Access
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