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DOE OSTI · 1969705

Magnetic phase diagram mapping in Fe 1- x Rh x composition-spread thin films

Yu, Heshan·Gao, Tieren·N’Diaye, A. T.·Arenholz, E.·Sarker, Suchismita·Mehta, Apurva·Zhang, Xiaohang·Takeuchi, Ichiro
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Abstract

We have fabricated high-quality polycrystalline Fe 1- x Rh x composition-spread thin films by cosputtering Fe and Rh, and investigated their structural and magnetic transformations as a systematic function of composition. With increasing Rh concentration, Fe 1-x Rh x thin film undergoes from an α' phase to a disordered γ phase and also shows a magnetic transition from a ferromagnetic phase to a paramagnetic phase. Vibrating-sample magnetometry and x-ray magnetic circular dichroism measurements show an antiferromagnetic-ferromagnetic transition in the range of 0.52 < x < 0.58 in the Fe 1- x Rh x composition gradient at room temperature. Based on our structural and magnetic property mapping, we construct a thin-film phase diagram of Fe 1- x Rh x . Compared to reported results in bulk alloys, the antiferromagnetic-ferromagnetic transition in the Fe 1- x Rh x thin films was found to occur at slightly higher Rh concentrations, while the boundary between the pure γ phase and the α'/ γ mixed phase region is shifted to the lower concentration Rh.

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36 MATERIALS SCIENCEferromagnetismmagnetic hysteresismagnetic materialsphase transitionssynchrotronsthin filmsx-ray diffractionx-ray magnetic circular dichroism spectroscopy

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Yu, Heshan, Gao, Tieren, N’Diaye, A. T., Arenholz, E., Sarker, Suchismita, Mehta, Apurva, Zhang, Xiaohang, Takeuchi, Ichiro. 2023-02-06. Magnetic phase diagram mapping in Fe 1- x Rh x composition-spread thin films. https://doi.org/10.1116/6.0002220

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