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arXiv · 2403.08582

Simultaneous mapping of magnetic and atomic structure for direct visualization of nanoscale magnetoelastic coupling

Abstract

Achieving a correlative measurement of both magnetic and atomic structures at the nanoscale is imperative to understand the fundamental magnetism of matters and for fostering the development of new magnetic nanomaterials. Conventional microscopy methods fall short in providing the two information simultaneously. Here, we develop a new approach to simultaneously map the magnetic field and atomic structure at the nanoscale using Lorentz 4-dimensional scanning transmission electron microscopy (Ltz-4D-STEM). This method enables precise measurement of the characteristic atomic and magnetic structures across an extensive field of view, a critical aspect for investigating real-world ferromagnetic materials. It offers a comprehensive visualization and statistical evaluation of the different structural information at a pixel-by-pixel correlation. The new method allows to directly visualize the magnetoelastic coupling and the resulting complex magnetization arrangement as well as the competition between magnetoelastic and magnetostatic energy. This approach opens new avenues for in-depth studying the structure-property correlation of nanoscale magnetic materials.

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Sangjun Kang, Maximilian Töllner, Di Wang, Christian Minnert, Karsten Durst, Arnaud Caron, Rafal E. Dunin-Borkowski, Jeffrey McCord, Christian Kübel, Xiaoke Mu. 2024-03-13. Simultaneous mapping of magnetic and atomic structure for direct visualization of nanoscale magnetoelastic coupling. https://arxiv.org/abs/2403.08582

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