Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, Netherlands.
Universität Hamburg, Center for Hybrid Nanostructures, Luruper Chaussee 149, 22761 Hamburg, Germany.
Phys Rev Lett. 2019 Oct 11;123(15):157201. doi: 10.1103/PhysRevLett.123.157201.
The stabilization of chiral magnetic domain walls and skyrmions has been attributed to the actively investigated Dzyaloshinskii-Moriya interaction. Recently, however, predictions were made that suggest dipolar interactions can also stabilize chiral domain walls and skyrmions, but direct experimental evidence has been lacking. Here we show that dipolar interactions can indeed stabilize chiral domain walls by directly imaging the magnetic domain walls using scanning electron microscopy with polarization analysis in archetype Pt/CoB/Ir thin film multilayers. We further demonstrate the competition between the Dzyaloshinskii-Moriya and dipolar interactions by imaging a reversal of the domain wall chirality as a function of the magnetic layer thickness. Finally, we suggest that this competition can be tailored by a Ruderman-Kittel-Kasuya-Yosida interaction. Our work therefore reveals that dipolar interactions play a key role in the stabilization of chiral spin textures. This insight will open up new routes towards balancing interactions for the stabilization of chiral magnetism.
手性磁畴壁和斯格明子的稳定归因于目前正在积极研究的 Dzyaloshinskii-Moriya 相互作用。然而,最近的预测表明,偶极相互作用也可以稳定手性畴壁和斯格明子,但缺乏直接的实验证据。在这里,我们通过在原型 Pt/CoB/Ir 薄膜多层结构中使用带有极化分析的扫描电子显微镜直接成像磁畴壁,证明了偶极相互作用确实可以稳定畴壁。我们进一步通过成像畴壁手性随磁层厚度的反转,证明了 Dzyaloshinskii-Moriya 相互作用和偶极相互作用之间的竞争。最后,我们提出这种竞争可以通过 Ruderman-Kittel-Kasuya-Yosida 相互作用来调节。因此,我们的工作表明,偶极相互作用在手性自旋结构的稳定中起着关键作用。这一见解将为平衡相互作用以稳定手磁开辟新途径。