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Register a new userDirect observation of the magnetic proximity effect in amorphous exchange-spring magnets by neutron reflectometry
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Atle Jorstad Qviller
Publication date
2018
fields
Physics
and research's language is
English
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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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