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DOE OSTI · 2567025

Magnetic skyrmionic structures with variable topological charges in engineered Dzyaloshinskii-Moriya interaction systems

Niu, Heng [Nanjing Univ. (China)] (ORCID:0000000153211387)·Yoon, Han Gyu [Kyung Hee Univ., Seoul (Korea, Republic of)]·Kwon, Hee Young [Korea Institute of Science and Technology (KIST), Seoul (Korea, Republic of)]·Cheng, Zhiyuan [Nanjing Univ. (China)]·Fu, Siqi [Nanjing Univ. (China)]·Zhu, Hongying [Nanjing Univ. (China)]·Miao, Bingfeng [Nanjing Univ. (China)] (ORCID:0000000230890695)·Sun, Liang [Nanjing Univ. (China)] (ORCID:0000000178259256)·Wu, Yizheng [Fudan Univ., Shanghai (China)] (ORCID:0000000292891271)·Schmid, Andreas K. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Molecular Foundry] (ORCID:0000000300353095)·Liu, Kai [Georgetown Univ., Washington, DC (United States)] (ORCID:0000000194136782)·Won, Changyeon [Kyung Hee Univ., Seoul (Korea, Republic of)] (ORCID:0000000159877411)·Ding, Haifeng [Nanjing Univ. (China)] (ORCID:0000000175240779)·Chen, Gong [Nanjing Univ. (China)] (ORCID:0000000251027487)
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Abstract

Magnetic skyrmionic structures, including magnetic skyrmions and antiskyrmions, are characterized by swirling spin textures with non-trivial topologies. They are featured with specific topological charges, Q , which are of crucial importance in determining their topological properties. Owing to the invariance of the chiral nature, it is generally believed that Q is conserved in a given magnetic skyrmionic structure and is hard to alter. Here, we experimentally realize the control of Q of magnetic skyrmionic structures at room temperature in a Dzyaloshinskii-Moriya interaction (DMI) platform with spatially alternating signs. Depending on how many times it crosses the interfaces between DMI regions with opposite signs, the magnetic skyrmionic structures possess different Q . Modifying the DMI energy landscape through chemisorbed oxygen, a magnetic topological transition is realized. This creation and manipulation of magnetic skyrmionic structures with controllable Q , in particular the DMI-stabilized thin-film antiskyrmions and high- Q skyrmionic structures, enables a new degree of freedom to control their dynamics via a novel DMI confinement effect. Our findings open up an unexplored avenue on various topological magnetic skyrmionic structures and their potential applications.

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Niu, Heng [Nanjing Univ. (China)] (ORCID:0000000153211387), Yoon, Han Gyu [Kyung Hee Univ., Seoul (Korea, Republic of)], Kwon, Hee Young [Korea Institute of Science and Technology (KIST), Seoul (Korea, Republic of)], Cheng, Zhiyuan [Nanjing Univ. (China)], Fu, Siqi [Nanjing Univ. (China)], Zhu, Hongying [Nanjing Univ. (China)], Miao, Bingfeng [Nanjing Univ. (China)] (ORCID:0000000230890695), Sun, Liang [Nanjing Univ. (China)] (ORCID:0000000178259256), Wu, Yizheng [Fudan Univ., Shanghai (China)] (ORCID:0000000292891271), Schmid, Andreas K. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Molecular Foundry] (ORCID:0000000300353095), Liu, Kai [Georgetown Univ., Washington, DC (United States)] (ORCID:0000000194136782), Won, Changyeon [Kyung Hee Univ., Seoul (Korea, Republic of)] (ORCID:0000000159877411), Ding, Haifeng [Nanjing Univ. (China)] (ORCID:0000000175240779), Chen, Gong [Nanjing Univ. (China)] (ORCID:0000000251027487). 2025-04-11. Magnetic skyrmionic structures with variable topological charges in engineered Dzyaloshinskii-Moriya interaction systems. https://doi.org/10.1038/s41467-025-58529-4

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