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 intrinsic $T_c$ of the embedded layer, with a range extending 50 .

中文翻译：

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通过中子反射法直接观察非晶态交换弹簧磁体中的磁性邻近效应

在这封信中，我们报告了通过使用中子反射法直接观察到非晶薄膜交换弹簧磁体中的磁性接近效应。交换弹簧磁体是一个三层，由两个铁磁层组成${Ť}_C$由铁磁层隔开，该铁磁层经设计具有明显较低的厚度 ${Ť}_C$比嵌入层 这使我们能够测量低磁场强度下的磁化深度分布${Ť}_C$材料处于铁磁或顺磁状态，而嵌入层是铁磁。在本征以上7 K处观察到明显的接近效应${Ť}_C$ 嵌入层的宽度为50埃。