摘要稀释反铁磁增强交换偏置效应的发现使得人为调控薄膜体系交换偏置场大小成为可能,但其内在的物理机制还存在着不少争议。在本论文中,我们采用微磁学理论,利用OOMMF和LLG软件进行模拟来研究反铁磁稀释效应对交换偏置的影响。67479
模拟结果显示,当添加非磁颗粒时,反铁磁表面的未补偿磁矩得到较大的增加,从而使得交换偏置场HE逐渐增大;但当非磁颗粒的稀释浓度到某一比例时,如果继续增加非磁颗粒,交换偏置场HE逐渐减小,其原因在于过高的稀释度,导致反铁磁表面未补偿磁矩的减少。
毕业论文关键词 交换偏置 微磁学 反铁磁稀释 模拟
毕业设计说明书(论文)外文摘要
Title The micromagnetic simulation of the antiferromagnetic dilution effect in the system of interlayer antiferromagnetic exchange bias
Abstract
The phenomenon that by diluting the antiferromagnetic can enhance the HE of thin films makes it possible to adjust magnitude of HE, but there still remains some controversies about its internal mechanism. In this paper, we use micromagnetic theory to study the influence of antiferromagnetic dilution effect on the exchange bias effect by the use of OOMMF and LLG simulation software.
The simulation results show that when adding non-magnetic particles, the uncompensated magnetic moment on the antiferromagnetic surface obtains a large increases, so that the exchange bias field HE increases; But when the dilution of the non-magnetic particles to a proportion, if it continues to increase non-magnetic particles, the exchange bias field HE decreases, the reason is that the high dilution leads to the decrease of uncompensated magnetic moment on the antiferromagnetic surface.
Keywords Exchange bias Micromagnetic Antiferromagnetic dilution Simulation
目 次
1 引言 1
1.1 磁学的发展历程 1
1.2 铁磁性、反铁磁性 2
1.3 反铁磁稀释效应 4
2 交换偏置 4
2.1 交换偏置概念 4
2.2 理论机制发展及其模型 6
2.3 交换偏置的基本特性 6
2.4 反铁磁稀释效应与交换偏置的关系 7
3 微磁学 8
3.1 微磁学简述 8
3.2 微磁学基本能量 9
3.3 能量最小化的基本处理方法与数值微磁学 14
4 微磁学软件 16
4.1 OOMMF 16
4.2 LLG Micromagnetics Simulator 17
5 模拟 18
5.1 OOMMF模拟 19
5.2 LLG模拟 22
6 实验分析 24
6.1 数据分析 24
6.2 实验的不足与分析 26
结论 28
致谢