Influence of film morphology on perpendicular magnetic anisotropy
Influence of film morphology on perpendicular magnetic anisotropy
复制标题
薄膜形貌对垂直磁各向异性的影响
DOI：
10.1103/physrevb.64.125406
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发表时间：
2001
影响因子：
3.7
通讯作者：
A. Hernando
中科院分区：
文献类型：
--
作者：
J. Camarero;J. Miguel;R. Miranda;V. Raposo;A. Hernando
Instituto de Magnetismo Aplicado '' Salvador Velayos，'' UCM-RENFE，P.O. Box 155，Las Rozas，E-28230-马德里，西班牙~接收于2001年2月25日;出版于2001年9月6日！永磁各向异性~PMA！出现在外延膜中主要是由于界面处的对称性破缺。结果，磁性层倾向于垂直磁化。随着薄膜厚度的增加，形状各向异性克服了这种界面贡献，并迫使样品磁化进入表面平面。我们表明，以前的实验研究的磁各向异性能在Co/Cu~111！由于Co膜表面粗糙度较大，导致Co-Cu界面各向异性值被低估。通过使用表面活性剂~Pb！为了辅助Co层的生长，我们能够制备厚度均匀且粗糙度可以忽略的Co膜和Cu/Co双层膜，并确定更精确的Co-Cu界面各向异性值。借助一个简单的模型计算，我们证明了粗糙度将显著影响PMA的实验测定值。DOI：10.1103/PhysRevB.64.125406 PACS编号：68.55.2a，75.30.Gw，75.70.Ak，81.15.2zI.介绍
Instituto de Magnetismo Aplicado ‘‘Salvador Velayos,’’ UCM-RENFE, P.O. Box 155, Las Rozas, E-28230-Madrid, Spain~Received 25 February 2001; published 6 September 2001!Perpendicular magnetic anisotropy ~PMA! appears in epitaxial films mainly due to the broken symmetry atthe interface. As a result, ultrathin magnetic layers tend to be perpendicularly magnetized. With increasing filmthickness, the shape anisotropy overcomes this interface contribution and forces the sample magnetization intothe surface plane. We show that previous experimental studies of the magnetic anisotropy energies in theCo/Cu~111! system are affected by the large roughness of the Co films, resulting in underestimated values forthe Co-Cu interface anisotropy. By using a surfactant~Pb! to assist the growth of Co layers we are able toprepare Co films and Cu/Co bilayers of homogeneous thickness and negligible roughness, and to determine amore accurate value for the Co-Cu interface anisotropy. With the aid of a simple model calculation, wedemonstrate that roughness will substantially affect experimentally determined values of PMA.DOI: 10.1103/PhysRevB.64.125406 PACS number~s!: 68.55.2a, 75.30.Gw, 75.70.Ak, 81.15.2zI. INTRODUCTION