Kai LITZIUS
Recently, the combination of 2-dimensional (2D) magnetism with the field of spintronics, i.e. the manipulation of magnetic states with electric currents, has started to gain much traction in modern solid-state physics. Furthermore, observations of magnetic skyrmions in 2D itinerant ferromagnets have been reported, opening further possibilities for technological implementation. However, the stability of the different magnetic states and morphological phases in FexGeTe2 remains an unresolved issue. In this work, we utilize real-space imaging to determine magnetic phase diagrams of exfoliated FexGeTe2 films. Our findings show besides complex, history-dependent magnetization states also that changes in the crystalline structure significantly alter the magnetic behavior. Most significant is the demonstration of spatially varying chemical and magnetic areas in quenched Fe5GeTe2, causing a complex energy landscape not suitable for domain wall and skyrmion dynamics, while annealed samples present themselves as highly homogenous. Ultimately, the choice of material and a proper nucleation mechanism result in the stabilization of a variety of (meta-) stable magnetic configurations, including skyrmions. These findings open novel perspectives for designing van der Waal heterostructure-based devices incorporating topological spin textures.
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[3] Chen H. et al. (2022) Revealing room temperature ferromagnetism in exfoliated Fe5GeTe2 flakes with quantum magnetic imaging. 2D Mater. 9, 025017