Two-dimensional characterization of three-dimensional magnetic bubbles in Fe3Sn2 nanostructures

We report differential phase contrast scanning transmission electron microscopy (TEM) of nanoscale magnetic objects in Kagome ferromagnet Fe3Sn2 nanostructures. This technique can directly detect the deflection angle of a focused electron beam, thus allowing clear identification of the real magnetic structures of two magnetic objects including three-ring and complex arch-shaped vortices in Fe3Sn2 by Lorentz-TEM imaging. Numerical calculations based on real material-specific parameters well reproduced the experimental results, showing that the magnetic objects can be attributed to integral magnetizations of two types of complex three-dimensional (3D) magnetic bubbles with depth-modulated spin twisting. Magnetic configurations obtained using the high-resolution TEM are generally considered as two-dimensional (2D) magnetic objects previously. Our results imply the importance of the integral magnetizations of underestimated 3D magnetic structures in 2D TEM magnetic characterizations.

Automated summary

This study used differential phase contrast scanning transmission electron microscopy to investigate nanoscale magnetic objects in Kagome ferromagnet Fe3Sn2 nanostructures, revealing that these magnetic objects can be attributed to the integral magnetizations of two types of complex 3D magnetic bubbles with depth-modulated spin twisting. While magnetic configurations obtained using high-resolution TEM are generally considered as two-dimensional, the results suggest the importance of the integral magnetizations of underestimated 3D magnetic structures in 2D TEM magnetic characterizations.