Formation of magnetic biskyrmions mediated by an intrinsic emergent monopole-antimonopole pair

• Published in: npj quantum materials Vol. 7; no. 1; pp. 1 - 6
• Main Authors: Wang, Cheng-Jie, Wang, Pengfei, Zhou, Yan, Wang, Wenhong, Shi, Fazhan, Du, Jiangfeng
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 12.08.2022; Nature Publishing Group; Nature Portfolio
• Subjects: 639/766/119/2792/4129; 639/766/119/2793; Anisotropy; Bubbles; Condensed Matter Physics; Geometry; Hypothetical particles; Laboratories; Magnetic properties; Monopoles; Particle theory; Phase transitions; Physics; Physics and Astronomy; Quantum Physics; Science; Simulation; Structural Materials; Surfaces and Interfaces; Thin Films; Topology
• ISSN: 2397-4648; 2397-4648
• DOI: 10.1038/s41535-022-00486-y

Various properties and potential technological applications of magnetic skyrmions have stimulated a flourishing interest in topological spin textures. Among them, biskyrmions with a rare topological charge of two are observed but their existence is still under debate. In this work, we present the formation of biskyrmion bubbles mediated by emergent monopoles via micromagnetic simulations. We find that biskyrmion bubbles and trivial bubbles share a unified three-dimensional structure, in which the relative position of an intrinsic emergent monopole-antimonopole pair dominates the two-dimensional topological property at the middle plane of magnetic uniaxial films. Biskyrmion bubbles can be transformed from trivial bubbles by the motion of emergent monopoles in confined geometry, paving the way for developing devices. These results highlight the three-dimensional aspect of skyrmion-related nanostructures and the versatile roles of emergent monopoles in topological spin textures.