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arXiv · 1104.0139

Tuning the magnetic properties of Co nanoparticles by Pt capping

A. Ebbing·O. Hellwig·L. Agudo·G. Eggeler·O. Petracic
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Abstract

We show that by capping Co nanoparticles with small amounts of Pt strong changes of the magnetic properties can be induced. The Co nanoparticles have a mean diameter of 2.7 nm. From magnetometry measurements we find that for zero and for small amounts of Pt (nominal thickness t(Pt) < 0.7 nm) the nanoparticles behave superparamagnetic like. With increasing t(Pt) the blocking temperature is enhanced from 16 up to 108 K. Capping with Pd yields comparable results. However, for values t(Pt) > 1 nm a strongly coupled state is encountered resembling a ferromagnet with a T_c approx. 400 K

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A. Ebbing, O. Hellwig, L. Agudo, G. Eggeler, O. Petracic. 2011-04-01. Tuning the magnetic properties of Co nanoparticles by Pt capping. https://doi.org/10.1103/physrevb.84.012405

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