Topological Spin Textures in an Insulating van der Waals Ferromagnet

Journal Article · Mon Mar 04 00:00:00 EST 2024 · Advanced Materials

DOI:https://doi.org/10.1002/adma.202311949· OSTI ID:2318569

Grebenchuk, Sergey ^[1]; McKeever, Conor ^[2]; Grzeszczyk, Magdalena ^[3]; Chen, Zhaolong ^[3]; Šiškins, Makars ^[3]; McCray, Arthur R. C. ^[4]; Li, Yue ^[5]; Petford‐Long, Amanda K. ^[6]; Phatak, Charudatta M. ^[6]; Ruihuan, Duan ^[7]; Zheng, Liu ^[8]; Novoselov, Kostya S. ^[1]; Santos, Elton J. G. ^[9]; Koperski, Maciej  ^[1]

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1. Institute for Functional Intelligent Materials National University of Singapore Singapore 117544 Singapore, Department of Materials Science and Engineering National University of Singapore Singapore 117575 Singapore
2. Institute for Condensed Matter Physics and Complex Systems School of Physics and Astronomy The University of Edinburgh Edinburgh EH9 3FD UK
3. Institute for Functional Intelligent Materials National University of Singapore Singapore 117544 Singapore
4. Materials Science Division Argonne National Laboratory Lemont IL 60439 USA, Applied Physics Program Northwestern University Evanston IL 60208 USA
5. Materials Science Division Argonne National Laboratory Lemont IL 60439 USA
6. Materials Science Division Argonne National Laboratory Lemont IL 60439 USA, Department of Materials Science and Engineering Northwestern University Evanston IL 60208 USA
7. School of Materials Science and Engineering Nanyang Technological University Singapore 639798 Singapore, CINTRA CNRS/NTU/THALES, UMI 3288, Research Techno Plaza Nanyang Technological University Singapore 639798 Singapore
8. School of Materials Science and Engineering Nanyang Technological University Singapore 639798 Singapore
9. Institute for Condensed Matter Physics and Complex Systems School of Physics and Astronomy The University of Edinburgh Edinburgh EH9 3FD UK, Higgs Centre for Theoretical Physics The University of Edinburgh Edinburgh EH9 3FD UK, Donostia International Physics Center (DIPC) 20018 Donostia‐San Sebastián Basque Country Spain

Abstract Generation and control of topological spin textures constitutes one of the most exciting challenges of modern spintronics given their potential applications in information storage technologies. Of particular interest are magnetic insulators, which due to low damping, absence of Joule heating and reduced dissipation can provide energy‐efficient spin‐textures platform. Here, it is demonstrated that the interplay between sample thickness, external magnetic fields, and optical excitations can generate a prolific paramount of spin textures, and their coexistence in insulating CrBr ₃ van der Waals (vdW) ferromagnets. Using high‐resolution magnetic force microscopy and large‐scale micromagnetic simulation methods, the existence of a large region in T‐B phase diagram is demonstrated where different stripe domains, skyrmion crystals, and magnetic domains exist and can be intrinsically selected or transformed to each‐other via a phase‐switch mechanism. Lorentz transmission electron microscopy unveils the mixed chirality of the magnetic textures that are of Bloch‐type at given conditions but can be further manipulated into Néel‐type or hybrid‐type via thickness‐engineering. The topological phase transformation between the different magnetic objects can be further inspected by standard photoluminescence optical probes resolved by circular polarization indicative of an existence of exciton‐skyrmion coupling mechanism. The findings identify vdW magnetic insulators as a promising framework of materials for the manipulation and generation of highly ordered skyrmion lattices relevant for device integration at the atomic level.

• Sponsoring Organization: USDOE
• Grant/Contract Number: DE‐AC02‐06CH11357
• OSTI ID: 2318569
• Journal Information: Advanced Materials, Journal Name: Advanced Materials; ISSN 0935-9648
• Publisher: Wiley Blackwell (John Wiley & Sons)
• Country of Publication: Germany
• Language: English