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Superparamagnetic behaviour of antiferromagnetic DyPO4 nanoparticles

T. G. Sorop·M. Evangelisti·M. Haase·L. J. de Jongh
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Abstract

We report on the low-temperature magnetic ac-susceptibility of antiferromagnetic DyPO4 nanoparticles with a very high surface to volume ratio. The results are interpreted in terms of superparamagnetic relaxation of the Neel vector arising from a relatively large number approx 0.2 Na of uncompensated spins probably existing on the surface of the nanoparticles. The activation energy of the relaxation process is found to be Ea / kB = (2.6+-0.1) K within a model taking into account the magnetic interaction between nanoparticles.

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T. G. Sorop, M. Evangelisti, M. Haase, L. J. de Jongh. 2003-04-01. Superparamagnetic behaviour of antiferromagnetic DyPO4 nanoparticles. https://doi.org/10.1016/j.jmmm.2003.12.507

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