（1. Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China）（2. School of Physics and Materials Engineering, Hefei Normal University, Hefei 230061, China）
Transmission electronic microscopy (TEM) has become one of the most advanced techniques to observe nanometric-sized magnetic domains, owing to its high spatial magnetic resolution and easy accessibility in integrating multiple physic fields. Here, we compared three techniques of TEM observing magnetic domains: Lorentz-TEM, electronic holography and differential phase contrast scanning TEM (DPCSTEM). Then we reviewed recent advances in magnetic domains imaging of a centrosymmetric magnet Fe3Sn2 by DPC-STEM. We demonstrated physical clarifications to “multiple topological states”, which are attributed to three-dimensional (3D) depth-modulated spin configurations, using DPC-STEM and 3D micromagnetic simulations. We then reported a new class of vortex-like spin configurations named “target bubble” and their field-driven magnetic evolutions in Fe3Sn2 nanodisks. Finally, we proposed a new strategy to design memory named Skyrmion-bubble-based memory, which utilizes Skyrmions and bubbles as binary bits “1” and “0”, respectively. Current-field-controlled topological Skyrmionbubble transformations have been also achieved. The novel magnetic domains and their intriguing electronic-magnetic properties shed by DPC-STEM are expected to facilitate advances in developing topology-related spintronic devices.