Jin Shuaizhao, Liu Yujia, Deng Zunyi, Wang Tingjun, Xu Shaoqing, Chen Yichong, Jiang Xingang, Liang Chaobo, Hong Jiawang, Cheong Sang-Wook, Wang Xueyun
School of Aerospace Engineering, Beijing Institute of Technology, Beijing, 100081, China.
Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, 08854, USA.
Adv Mater. 2025 Jul;37(29):e2501935. doi: 10.1002/adma.202501935. Epub 2025 May 9.
Magnetic structures are profoundly influenced by mechanical deformation. In particular, strain has been employed to achieve the reconstruction of magnetic domains, paving a mechanical pathway to manipulate magnetic domains. However, experimentally applied strains typically exhibit non-uniform distributions. Therefore, how to distinguish the role of non-uniform strains (strain gradients) and uniform strains is crucial for understanding the mechanical manipulation of magnetic structures. Here, by directly comparing to strain tuning, it is revealed that strain gradient induced by mechanical wrinkles is critical for magnetic domain manipulation in van der Waals ferromagnet FeGaTe. A ground-state labyrinthine domain transforms into a skyrmion state in the presence of an in-plane strain gradient. Additionally, an asymmetric evolutionary behavior of the magnetic domain occurs on both sides of wrinkle peaks. Theoretical simulations uncover that though opposite in-plane strain gradient hosts C rotational symmetry, this asymmetric domain evolution can be achieved through the coupling of perpendicular magnetic anisotropy and Dzyaloshinskii-Moriya interaction. The finding highlights the vital role of strain gradient in manipulating magnetic properties, and also offers a new mechanism for generating field-free skyrmion.
磁性结构受到机械变形的深刻影响。特别是，应变已被用于实现磁畴的重构，为操纵磁畴开辟了一条机械途径。然而，实验施加的应变通常呈现非均匀分布。因此，如何区分非均匀应变（应变梯度）和均匀应变的作用对于理解磁性结构的机械操纵至关重要。在此，通过与应变调谐直接比较发现，机械皱纹诱导的应变梯度对于范德华铁磁体FeGaTe中的磁畴操纵至关重要。在存在面内应变梯度的情况下，基态迷宫畴转变为斯格明子态。此外，在皱纹峰值两侧会出现磁畴的不对称演化行为。理论模拟发现，尽管相反的面内应变梯度具有C旋转对称性，但这种不对称的畴演化可以通过垂直磁各向异性和Dzyaloshinskii-Moriya相互作用的耦合来实现。这一发现突出了应变梯度在操纵磁性特性中的重要作用，也为产生无场斯格明子提供了一种新机制。
