Observation of multi-order polar radial vortices and their topological transition

作者：Wan‐Rong Geng, Xiangwei Guo, Yin‐Lian Zhu, Desheng Ma, Yun‐Long Tang, Yujia Wang, Yongjun Wu, Zijian Hong, Xiuliang Ma · 发表于：Nature Communications · 年份：2025 · DOI：10.1038/s41467-025-58008-w · 被引用次数：8 · 研究领域：Multiferroics and related materials、Magnetic properties of thin films、Magneto-Optical Properties and Applications

Abstract Topological states have garnered enormous interest in both magnetic and ferroelectric materials for promising candidates of next-generation information carriers. Especially, multi-order topological structures with modulative topological charges are promising for multi-state storage. Here, by engineering boundary conditions, we directly observe the self-assembly two-order ferroelectric radial vortices in high-density BiFeO 3 nanostructures. The as-observed two-order radial vortex features a doughnut-like out-of-plane polarization distribution and four-quadrant in-plane distribution, with the topological charge of Q = 0. Systematic dimensional control of the BiFeO 3 nanostructures reveals size-dependent stabilization of distinct topological states, from elementary one-order to complex three-order radial vortices, which is further rationalized by phase-field simulations. The transition between different topological states with various topological charges is also realized under an external electric field. This study opens up an avenue for generating configurable polar topological states, offering potential advancements in designing high-performance multi-state memory devices.