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arXiv · 1008.1956

Anomalous magnetisation in a Fe_3Pt-FeRh film occurring at T~120 K in the field-cooled-cooling curves for low magnetic fields

S. Salem-Sugui, Jr·A. D. Alvarenga·R. D. Noce·C. Salazar Mejia·H. Salim·F. G. Gandra
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Abstract

We report on an anomalous magnetization observed with temperature for low magnetic fields applied in the plane of a film formed by a thin layer of Fe-Rh deposited on a thin foil of ordered Fe$_3$Pt. The anomalous effect resembles a metamagnetic transition and occur only in the field-cooled-cooling magnetization curve at temperatures near 120 K. We also observe an aging effect which broads the metamagnetic-like transition suggesting the existence of Fe-Rh antiferromagnetic clusters which apparently are too small to be detected by the x-ray diffraction.The X-Ray diffractogram obtained in the Fe-Rh surface of the film do not show the Fe-Rh antiferromagnetic phase (a=2.98 $\AA$) but peaks at same locations of those found for the pure ordered Fe$_3$Pt film (a=3.72 $\AA$)

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S. Salem-Sugui, Jr, A. D. Alvarenga, R. D. Noce, C. Salazar Mejia, H. Salim, F. G. Gandra. 2010-08-11. Anomalous magnetisation in a Fe_3Pt-FeRh film occurring at T~120 K in the field-cooled-cooling curves for low magnetic fields. https://arxiv.org/abs/1008.1956

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