School of Physics, University of Western Australia, Crawley, WA6009, Australia.
Phys Rev Lett. 2011 Sep 16;107(12):127201. doi: 10.1103/PhysRevLett.107.127201. Epub 2011 Sep 12.
A detailed investigation of magnetic impurity-mediated interlayer exchange coupling observed in Cu(0.94)Mn(0.06)/Co multilayers using polarized neutron reflectometry and magnetic x-ray techniques is reported. Excellent descriptions of temperature and magnetic field dependent biquadratic coupling are obtained using a variant of the loose spin model that takes into account the distribution of the impurity Mn ions in three dimensions. Positional disorder of the magnetic impurities is shown to enhance biquadratic coupling via a new contribution J(2)(fluct), leading to a temperature dependent canting of magnetic domains in the multilayer. These results provide measurable effects on RKKY coupling associated with the distribution of impurities within planes parallel to the interfaces.
使用极化中子反射和磁 X 射线技术对 Cu(0.94)Mn(0.06)/Co 多层膜中观察到的磁性杂质介导的层间交换耦合进行了详细研究。使用考虑杂质 Mn 离子在三维中分布的松散自旋模型的变体，得到了对温度和磁场依赖的双二次耦合的极好描述。通过新的贡献 J(2)(fluct)，磁性杂质的位置无序被证明增强了双二次耦合，导致多层中磁畴的温度相关倾斜。这些结果提供了与平行于界面的平面内杂质分布相关的 RKKY 耦合的可测量影响。
