Single spin ensemble model for the change of unidirectional anisotropy constant by annealing on polycrystalline ferromagnetic/ antiferromagnetic bilayers
Single spin ensemble model for the change of unidirectional anisotropy constant by annealing on polycrystalline ferromagnetic/ antiferromagnetic bilayers
复制标题
通过多晶铁磁/反铁磁双层退火改变单向各向异性常数的单自旋系综模型
DOI：
10.1063/1.373214
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发表时间：
2000
影响因子：
3.2
通讯作者：
M. Takahashi
中科院分区：
文献类型：
--
作者：
M. Tsunoda;M. Takahashi
提出了交换耦合多晶铁磁/反铁磁（F/AF）双层模型，以讨论热退火引起双层单向各向异性常数（JK）变化的机制。 AF层被视为AF颗粒的聚集体，其磁各向异性轴以二维随机分布位于膜平面内。针对 AF 颗粒计算了有关 AF 自旋方向的两个稳定状态。确定热平衡状态下各状态下AF晶粒的数量，即可获得系统的总能量，从而提供F/AF双层的磁化曲线和磁矩曲线。计算结果表明，JK 随着平衡温度的升高而降低，这是由于 AF 晶粒各自自旋排列的概率函数发生了变化。我们得出的结论是，JK 的变化并不一定需要微观结构和内在性能的任何变化...
A model for the exchange coupled polycrystalline ferromagnetic/antiferromagnetic (F/AF) bilayers is proposed in order to discuss the mechanism of the change of the unidirectional anisotropy constant (JK) of the bilayers by thermal annealing. The AF layer is treated as an aggregation of the AF grains whose magnetic anisotropy axes lay in the film plane with two-dimensionally random distribution. Two stable states concerning the direction of the AF spins are calculated for the AF grain. Determining the populations of the AF grains in each state in thermal equilibrium, total energy of the system is obtained, which provides the magnetization curves and the magnetic torque curves of the F/AF bilayers. The calculated results show the reduction of JK with increasing the equilibrium temperature, which is due to the changes of the probability functions for the respective spin alignments of the AF grain. We conclude that the changes in JK do not necessarily need any changes of the microstructure and the intrinsic p...