退火态Pt/Mn/Fe三层膜中的结构相变

Structural phase transformations in annealed Pt/Mn/Fe trilayers.

作者信息

Kruhlov I O, Shamis O V, Schmidt N Y, Karpets M V, Gulyas S, Hadjixenophontos E, Burmak A P, Sidorenko S I, Katona G L, Schmitz G, Albrecht M, Vladymyrskyi I A

机构信息

Metal Physics Department, National Technical University of Ukraine, 'Igor Sikorsky Kyiv Polytechnic Institute', Prospect Peremogy 37, 03056 Kyiv, Ukraine.

Institute of Physics, University of Augsburg, Universitätsstraße 1, D-86159 Augsburg, Germany.

出版信息

J Phys Condens Matter. 2020 Jun 17;32(36). doi: 10.1088/1361-648X/ab9269.

DOI:10.1088/1361-648X/ab9269

PMID:32396885

Abstract

Thermally-activated phase transitions in Pt/Mn/Fe thin films were investigated by a combination of x-ray diffraction, transmission electron microscopy, secondary neutral mass spectrometry depth profiling, atomic force microscopy, and magnetic properties measurements. Post-annealing was carried out in vacuum to different temperatures up to 620 °C. Initially, at temperatures between 280 °C-450 °C first L1-MnPt is formed at the Mn/Pt interface followed by the most likely formation of metastable bcc FePt, which gets transformed by further annealing to fcc FePt and eventually to chemically ordered L1-FePt. The final product after annealing at 620 °C consists of two interesting phases, which are relevant for spintronic applications, antiferromagnetic L1-MnPt with addition of Fe and ferromagnetic L1-FePt, consistent with the initial element composition.

摘要

通过结合X射线衍射、透射电子显微镜、二次中性质谱深度剖析、原子力显微镜和磁性测量等方法，对Pt/Mn/Fe薄膜中的热激活相变进行了研究。在真空中进行后退火，温度高达620℃。最初，在280℃至450℃之间的温度下，首先在Mn/Pt界面形成L1-MnPt，随后最有可能形成亚稳体心立方FePt，通过进一步退火将其转变为面心立方FePt，最终转变为化学有序的L1-FePt。在620℃退火后的最终产物由两个有趣的相组成，这两个相与自旋电子学应用相关，即添加了Fe的反铁磁L1-MnPt和铁磁L1-FePt，这与初始元素组成一致。