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arXiv · 1804.01479

Direct observation of the magnetic proximity effect in amorphous exchange-spring magnets by neutron reflectometry

A. J. Qviller·F. Magnus·B. J. Kirby·B. Hjörvarsson·C. Frommen·B. C. Hauback
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Abstract

In this letter we report a direct observation of a magnetic proximity effect in an amorphous thin film exchange-spring magnet by the use of neutron reflectometry. The exchange-spring magnet is a trilayer consisting of two ferromagnetic layers with high $T_c$'s separated by a ferromagnetic layer, which is engineered to have a significantly lower $T_c$ than the embedding layers. This enables us to measure magnetization depth profiles at which the low $T_c$ material is in a ferromagnetic or paramagnetic state, while the embedding layers are ferromagnetic. A clear proximity effect is observed 7 K above the $T_c$ of the embedded layer, with a range extending 50 $\unicode{xC5}$.

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A. J. Qviller, F. Magnus, B. J. Kirby, B. Hjörvarsson, C. Frommen, B. C. Hauback. 2018-04-04. Direct observation of the magnetic proximity effect in amorphous exchange-spring magnets by neutron reflectometry. https://doi.org/10.1103/physrevmaterials.4.104404

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