Pt插层对NiFe/FeMn薄膜交换耦合的影响
摘 要：采用磁控溅射方法制备了以Pt为缓冲层和保护层的NiFe/FeMn薄膜.在NiFe/FeMn界面插入Pt,发现交换偏置场(Hex)随着插层Pt厚度(tPt)的增加而减小.一个重要的现象是当Pt插层厚度为0.4nm时,在Het-tPt衰减曲线并非单纯指数下降,而是出现一个"凸起".通过对样品磁矩随Pt插层厚度的变化规律进行分析,发现随Pt插层厚度的增加,样品的磁矩先逐渐增大,然后又有所下降,并且稳定在某一值;表明在样品制备过程中,NiFe与FeMn之间的相互作用(如界面反应),使得在NiFe/FeMn界面存在磁死层,Pt的插入抑制了NiFe/FeMn界面磁死层的产生,有利于交换耦合;另一方面,Pt的插入隔离了NiFe和FeMn的直接接触,使得FeMn对NiFe的钉扎作用减弱,不利于交换耦合.两个方面的共同作用,使得当Pt插层为某一合适厚度时,Hex-tPt曲线出现"凸起".
关键词：交换耦合;Pt插层;磁死层
分类号：O484.4+3 文献标识码：A
文章编号：1672-7126(2008)增刊-005-04
Pt Spacer and Exchange Coupling between NiFe and FeMn Layers
Jin Chuan Liu Yang Li Minghua Yu Guanghua
基金项目：国家自然科学基金(No.50471093,50671008);北京市自然科学基金(No.2052014)和教育部"新世纪优秀人才支持计划"(No.NCET-04-0104)资助课题
作者简介：于广华,联系人:E-mail:ghyu＠mater.astb.edu.cn
作者单位：金川（北京科技大学材料物理与化学系,北京,100083）
刘洋（北京科技大学材料物理与化学系,北京,100083）
李明华（北京科技大学材料物理与化学系,北京,100083）
于广华（北京科技大学材料物理与化学系,北京,100083）
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