Field-induced Néel vector bi-reorientation of a ferrimagnetic insulator in the vicinity of compensation temperature
Field-induced Néel vector bi-reorientation of a ferrimagnetic insulator in the vicinity of compensation temperature
复制标题
补偿温度附近亚铁磁绝缘体的场感应尼尔矢量双向重定向
DOI：
10.1088/1674-1056/abbbef
复制
发表时间：
2021
影响因子：
1.7
通讯作者：
Lifan Zhou
中科院分区：
文献类型：
--
作者：
Peng Wang;Hui Zhao;Zhongzhi Luan;Siyu Xia;Tao Feng;Lifan Zhou
系统研究了铂/Gd3Fe5O12(GdIG)双层膜的自旋霍尔磁电阻(SMR)效应。在GdIG的磁化补偿点(Tm)附近，SMR的符号随着磁场的增加发生两次变化。然而，传统的SMR理论预测了重金属膜与铁磁或反铁磁膜接触构成的异质结中的不变SMR符号。我们的结论是，这是因为Gd亚晶格的磁矩显著增强，而Fe亚晶格的磁矩在相对较大的场下保持不变，这意味着在Tm处感应出较小的净磁矩，结果是在自旋-翻转相变后，Néel矢量与场对齐，这意味着Néel矢量产生了双向重新取向。基于Néel理论和SMR理论的理论计算也支持我们的结论。我们的发现表明，亚铁磁体的Néel矢量方向可以通过Tm周围相对较低的外场在很大范围内进行调谐。
The spin Hall magnetoresistance (SMR) effect in Pt/Gd3Fe5O12 (GdIG) bilayers was systematically investigated. The sign of SMR changes twice with increasing magnetic field in the vicinity of the magnetization compensation point (T. M) of GdIG. However, conventional SMR theory predicts the invariant SMR sign in the heterostructure composed of a heavy metal film in contact with a ferromagnetic or antiferromagnetic film. We conclude that this is because of the significant enhancement of the magnetic moment of the Gd sub-lattice and the unchanged moment of the Fe sub-lattice with a relatively large field, meaning that a small net magnetic moment is induced at T. M. As a result, the Néel vector aligns with the field after the spin-flop transition, meaning that a bi-reorientation of the Néel vector is produced. Theoretical calculations based on the Néel’s theory and SMR theory also support our conclusions. Our findings indicate that the Néel-vector direction of a ferrimagnet can be tuned across a wide range by a relatively low external field around T. M.