Magnetic 2D materials enable novel tuning options of magnetism. As an example, the van der Waals material FePS3, a zigzag-type intralayer antiferromagnet, exhibits very strong magnetoelastic coupling due to the different bond lengths along different ferromagnetic and antiferromagnetic coupling directions enabling elastic tuning of magnetic properties. The likely cause of the length change is the intricate competition between direct exchange of the Fe atoms and superexchange via the S and P atoms. To elucidate this interplay, we study the band structure of exfoliated FePS3 by mu m scale ARPES (Angular Resolved Photoelectron Spectroscopy), both, above and, for the first time, below the Neel temperature TN. We find three characteristic changes across TN. They involve S 3p-type bands, Fe 3d-type bands and P 3p-type bands, respectively, as attributed by comparison with density functional theory calculations (DFT+U). This highlights the involvement of all the atoms in the magnetic phase transition providing independent evidence for the intricate exchange paths.
@article{arxiv.2408.12896,
title = {Identifying band structure changes of FePS3 across the antiferromagnetic phase transition},
author = {Benjamin Pestka and Jeff Strasdas and Gustav Bihlmayer and Adam K. Budniak and Marcus Liebmann and Niklas Leuth and Honey Boban and Vitaliy Feyer and Iulia Cojocariu and Daniel Baranowski and Simone Mearini and Yaron Amouyal and Lutz Waldecker and Bernd Beschoten and Christoph Stampfer and Lukasz Plucinski and Efrat Lifshitz and Peter Kratzer and Markus Morgenstern},
journal= {arXiv preprint arXiv:2408.12896},
year = {2024}
}