Asymmetric depinning of chiral domain walls in ferromagnetic trilayers
Asymmetric depinning of chiral domain walls in ferromagnetic trilayers
复制标题
铁磁三层中手性畴壁的不对称脱钉
DOI：
10.1103/physrevb.102.174433
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发表时间：
2020
影响因子：
3.7
通讯作者：
P. Gambardella
中科院分区：
文献类型：
--
作者：
M. D. de Jong;C. Avci;A. Hrabec;P. Gambardella
我们证明了由非磁性间隔层隔开的两个铁磁层之间的耦合可以用来控制畴壁的脱落和诱导单向畴壁传播。我们研究了CoFeB/Ti/CoFeB三层，其中顶层CoFeB层磁化易轴为平面外，底层CoFeB层磁化易轴为平面内。利用磁光Kerr效应显微镜，我们发现垂直磁化的CoFeB层中畴壁的脱剥落受到面内层磁化方向的影响，从而引起场驱动的不对称畴扩展。这种效应是由于畴壁内部磁化强度与面内CoFeB层磁化强度之间的磁耦合，打破了垂直CoFeB层中上下和上下的同手性Neel畴壁的对称性。微磁模拟支持这些发现，表明层间耦合在畴壁中反对或支持Dzyaloshinskii-Moriya相互作用，从而在脱壳场中产生不平衡。这种效应还允许人为地控制缺乏强Dzyaloshinskii-Moriya相互作用的磁层中畴壁的手性和动力学。
We show that the coupling between two ferromagnetic layers separated by a nonmagnetic spacer can be used to control the depinning of domain walls and induce unidirectional domain wall propagation. We investigated CoFeB/Ti/CoFeB trilayers where the easy axis of the magnetization of the top CoFeB layer is out-of-plane and that of the bottom layer is in-plane. Using Magneto-optic Kerr effect microscopy, we find that the depinning of a domain wall in the perpendicularly magnetized CoFeB layer is influenced by the orientation of the magnetization of the in-plane layer, which gives rise to a field-driven asymmetric domain expansion. This effect occurs due to the magnetic coupling between the internal magnetization of the domain wall and the magnetization of the in-plane CoFeB layer, which breaks the symmetry of up-down and down-up homochiral Neel domain walls in the perpendicular CoFeB layer. Micromagnetic simulations support these findings by showing that the interlayer coupling either opposes or favors the Dzyaloshinskii-Moriya interaction in the domain wall, thereby generating an imbalance in the depinning fields. This effect also allows for artificially controlling the chirality and dynamics of domain walls in magnetic layers lacking a strong Dzyaloshinskii-Moriya interaction.
影响因子：
38.3
作者：
Avci, Can Onur;Rosenberg, Ethan;Beach, Geoffrey S. D.
通讯作者：
Beach, Geoffrey S. D.
影响因子：
41.2
作者：
Han, Dong-Soo;Lee, Kyujoon;Klaeui, Mathias
通讯作者：
Klaeui, Mathias