Berit Hansen Goodge
Dynamically tunable properties such as magnetic textures have many potential applications for next-generation information and communication technologies ranging from spintronics to broadband resonators. One promising class of materials are intercalated transition metal dichalcogenides (TMDs), in which a wide range of electronic and magnetic phases which can be tuned by varying the host lattice or the species, amount, and ordering of intercalants [1]. For example, metal intercalants such as iron, chromium, or vanadium can be hosted within metallic transition metal dichalcogenides (TMDs) such as TaS2 and NbS2, giving rise to a host of magnetic behaviors including chiral helical magnetism tunable by both spin-orbit coupling of the host TMD compound and external magnetic fields [3]. Some of these compounds can be stabilized directly through bulk synthesis methods such as chemical vapor transport, but alternative methods to actively and controllably introduce intercalant ions into two-dimensional (2D) TMD crystals offer the potential for fabricating bespoke heterostructures and devices with exquisitely tailored properties down to the low-dimensional limit [3-5]. In all cases, atomic-scale details of intercalant ordering and valence are imperative for understanding the rich behaviors in these systems. With access to these relevant order parameters – lattice, spin, and charge – with deep-sub-Å resolution, the scanning transmission electron microscope (STEM) is a powerful tool to probe the chemical framework of these compounds and its impact on their physical properties. Here I will discuss recent progress in understanding intercalated van der Waals magnets from the perspective of the atomic lattice, and how insights to the atomic lattice dovetail with synthesis and theory to advance our understanding and control in this rich class of materials.
[1] Xie, et al. J. Am. Chem. Soc. 144, 9525− 9542 (2022).[2] Goodge*, Gonzalez*, Xie, Bediako. ACS Nano 17 (20), 19865–19876 (2023).
[3] Husremović, et al. J. Am. Chem. Soc. 144, 12167−12176 (2022).
[4] Husremović, et al. Nature Communications 14, 6031 (2023).
[5] Husremović, et al. Nature Communications 16:1208 (2025).