Lin Weiwei, Chen Kai, Zhang Shufeng, Chien C L
Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, USA.
Department of Physics, University of Arizona, Tucson, Arizona 85721, USA.
Phys Rev Lett. 2016 May 6;116(18):186601. doi: 10.1103/PhysRevLett.116.186601. Epub 2016 May 5.
We report a large enhancement of thermally injected spin current in normal metal (NM)/antiferromagnet (AF)/yttrium iron garnet (YIG), where a thin AF insulating layer of NiO or CoO can enhance the spin current from YIG to a NM by up to a factor of 10. The spin current enhancement in NM/AF/YIG, with a pronounced maximum near the Néel temperature of the thin AF layer, has been found to scale linearly with the spin-mixing conductance at the NM/YIG interface for NM=3d, 4d, and 5d metals. Calculations of spin current enhancement and spin mixing conductance are qualitatively consistent with the experimental results.
我们报道了在正常金属（NM）/反铁磁体（AF）/钇铁石榴石（YIG）中热注入自旋电流的大幅增强，其中薄的NiO或CoO反铁磁绝缘层可将从YIG到NM的自旋电流增强高达10倍。已发现NM/AF/YIG中的自旋电流增强在薄AF层的奈尔温度附近有明显的最大值，对于NM为3d、4d和5d金属，其与NM/YIG界面处的自旋混合电导呈线性比例关系。自旋电流增强和自旋混合电导的计算与实验结果在定性上是一致的。
