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Updated: Mar 19, 2026
Scanning SQUID Study of Vortex Manipulation by Local Contact
Published on: February 1, 2017
Homotopy-Theoretic Study &Atomic-Scale Observation of Vortex Domains in Hexagonal Manganites
Jun Li1,2, Fu-Kuo Chiang1,3, Zhen Chen1,2
1Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
Abstract:
Essential structural properties of the non-trivial "string-wall-bounded" topological defects in hexagonal manganites are studied through homotopy group theory and spherical aberration-corrected scanning transmission electron microscopy. The appearance of a "string-wall-bounded" configuration in RMnO3 is shown to be strongly linked with the transformation of the degeneracy space. The defect core regions (~50 Å) mainly adopt the continuous U(1) symmetry of the high-temperature phase, which is essential for the formation and proliferation of vortices. Direct visualization of vortex strings at atomic scale provides insight into the mechanisms and macro-behavior of topological defects in crystalline materials.
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