摘　要：采用磁控濺射方法制備了以Pt為緩沖層和保護(hù)層的NiFe/FeMn薄膜.在NiFe/FeMn界面插入Pt,發(fā)現(xiàn)交換偏置場(chǎng)(Hex)隨著插層Pt厚度(tPt)的增加而減小.一個(gè)重要的現(xiàn)象是當(dāng)Pt插層厚度為0.4nm時(shí),在Het-tPt衰減曲線并非單純指數(shù)下降,而是出現(xiàn)一個(gè)"凸起".通過對(duì)樣品磁矩隨Pt插層厚度的變化規(guī)律進(jìn)行分析,發(fā)現(xiàn)隨Pt插層厚度的增加,樣品的磁矩先逐漸增大,然后又有所下降,并且穩(wěn)定在某一值;表明在樣品制備過程中,NiFe與FeMn之間的相互作用(如界面反應(yīng)),使得在NiFe/FeMn界面存在磁死層,Pt的插入抑制了NiFe/FeMn界面磁死層的產(chǎn)生,有利于交換耦合;另一方面,Pt的插入隔離了NiFe和FeMn的直接接觸,使得FeMn對(duì)NiFe的釘扎作用減弱,不利于交換耦合.兩個(gè)方面的共同作用,使得當(dāng)Pt插層為某一合適厚度時(shí),Hex-tPt曲線出現(xiàn)"凸起".

關(guān)鍵詞：交換耦合;Pt插層;磁死層

分類號(hào)：O484.4+3　文獻(xiàn)標(biāo)識(shí)碼：A

文章編號(hào)：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　

      基金項(xiàng)目：國(guó)家自然科學(xué)基金(No.50471093,50671008);北京市自然科學(xué)基金(No.2052014)和教育部"新世紀(jì)優(yōu)秀人才支持計(jì)劃"(No.NCET-04-0104)資助課題
作者簡(jiǎn)介：于廣華,聯(lián)系人:E-mail:ghyu＠m(xù)ater.astb.edu.cn

作者單位：金川（北京科技大學(xué)材料物理與化學(xué)系,北京,100083）
　　　　　劉洋（北京科技大學(xué)材料物理與化學(xué)系,北京,100083）
　　　　　李明華（北京科技大學(xué)材料物理與化學(xué)系,北京,100083）
　　　　　于廣華（北京科技大學(xué)材料物理與化學(xué)系,北京,100083）

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