Mapping domain disorder in exchange-biased magnetic multilayers
Mapping domain disorder in exchange-biased magnetic multilayers
复制标题
映射交换偏置磁性多层中的磁畴无序
DOI：
10.1103/physrevb.66.024437
复制
发表时间：
2002
影响因子：
3.7
通讯作者：
B. Hickey
中科院分区：
文献类型：
--
作者：
C. Marrows;S. Langridge;Mannan Ali;A. Hindmarch;D. Dekadjevi;S. Foster;B. Hickey
交换各向异性发生在反铁磁 (AF) 层和铁磁层之间的界面处，并导致铁磁体磁滞回线沿场轴位移。我们进行了非镜面中子反射测量，以表征由 FeMn 交换偏置的 Co 层中的域结构。这使我们能够确定 Co 层的磁畴方向分布和横向磁相关长度作为场的函数，并在两种不同的热准备状态下进行交换偏置：高场冷却和零场冷却。我们发现，可逆交换偏置层的特征是非常短（亚微米）的磁长度尺度，表明在高于阻断温度的温度下进行交流退磁后，磁畴比铁磁体中的磁畴小得多。这表明整个界面上的偏压在空间上并不均匀，强调了 AF 自旋结构的复杂性。
Exchange anisotropy occurs at the interface between an anti ferromagnetic (AF) layer and a ferromagnetic layer, and results in a ferromagnet hysteresis loop displaced along the field axis. We have performed off-specular neutron reflectometry in order to characterize the domain structure in Co layers that are exchange biased by FeMn. This allows us to determine the domain direction distributions and lateral magnetic correlation lengths for the Co layers as a function of field with the exchange bias in two different thermally prepared states: high field cooled and zero field cooled. We find that a reversing exchange-biased layer is characterized by a very short (submicron) magnetic lengthscale, indicating domains much smaller than those in the ferro-magnet after ac demagnetization at temperatures above the blocking temperature. This indicates that the bias is not spatially uniform across the entire interface, underlining the complexity of the AF spin structure.