Department of Physics, South China University of Technology, Guangzhou 510640, People's Republic of China.
J Phys Condens Matter. 2012 Jul 11;24(27):276002. doi: 10.1088/0953-8984/24/27/276002. Epub 2012 Jun 19.
The influence of non-magnetic defects on the exchange bias (EB) of ferromagnet (FM)/antiferromagnet (AFM) core/shell nanoparticles is studied by Monte Carlo simulations. It is found that the EB can be tuned by defects in different positions. Defects at both the AFM and FM interfaces reduce the EB field while they enhance the coercive field by decreasing the effective interface coupling. However, the EB field and the coercive field show respectively a non-monotonic and a monotonic dependence on the defect concentration when the defects are located inside the AFM shell, indicating a similar microscopic mechanism to that proposed in the domain state model. These results suggest a way to optimize the EB effect for applications.
通过蒙特卡罗模拟研究了非磁性缺陷对铁磁（FM）/反铁磁（AFM）核/壳纳米粒子的交换偏置（EB）的影响。结果表明，EB 可以通过不同位置的缺陷进行调节。在 AFM 和 FM 界面处的缺陷会降低 EB 场，同时通过减小有效界面耦合来提高矫顽力。然而，当缺陷位于 AFM 壳内时，EB 场和矫顽力场分别表现出非单调和单调的依赖于缺陷浓度的关系，这表明存在类似于畴态模型中提出的微观机制。这些结果为应用提供了优化 EB 效应的方法。
