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arXiv · 2601.19181

Mapping Metastable Magnetic Textures in (Fe0.5Co0.5)5GeTe2 with in-situ Lorentz Transmission Electron Microscopy

Reed Yalisove·Hongrui Zhang·Xiang Chen·Fanhao Meng·Jie Yao·Robert Birgeneau·Ramamoorthy Ramesh·Mary C. Scott
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Abstract

Topologically protected magnetic textures are a promising route to low-energy control of magnetism, but they are most often studied away from ambient conditions, typically at low temperatures and high magnetic fields. Here we use in-situ Lorentz transmission electron microscopy with control of temperature and magnetic field to investigate the skyrmion metastability in (Fe0.5Co0.5)5GeTe2 (FCGT). By field-cooling FCGT in magnetic fields of different magnitude to different base temperatures and then removing the applied field, we create meta(stable) zero-field magnetic states. We use this method to build a phase diagram of the zero-field metastable spin structures in FCGT, which will be critical for selecting the desired topologically-protected spin state for future studies to manipulate magnetism with stimuli such as electric current, electric field, mechanical strain, and more.

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Reed Yalisove, Hongrui Zhang, Xiang Chen, Fanhao Meng, Jie Yao, Robert Birgeneau, Ramamoorthy Ramesh, Mary C. Scott. 2026-01-27. Mapping Metastable Magnetic Textures in (Fe0.5Co0.5)5GeTe2 with in-situ Lorentz Transmission Electron Microscopy. https://arxiv.org/abs/2601.19181

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