Spin-orbital excitations encoding the magnetic phase transition in the van der Waals antiferromagnet FePS3
Van der Waals (vdW) materials are featuring intertwined electronic order and collective phenomena. Elucidating the dynamics of the elementary excitations within the fundamental electronic degrees of freedom is of paramount importance. Here we performed resonant inelastic X-ray scattering (RIXS) to elaborate the spin-orbital excitations of the vdW antiferromagnet FePS<sub>3</sub> and their role for magnetism. We observed the spectral enhancement of spin-orbital multiplet excitations at about ~100 and ~220 meV, as well as the quasielastic response, when entering the antiferromagnetic phase with an order-parameter-like evolution in temperature. By comparing with model calculations, we discovered the trigonal lattice distortion, spin-orbit interaction and metal-ligand charge-transfer to be essential for these emergent excitations. We further reveal their spectral robustness down to the few atomic-layer limit by mechanical exfoliation, in accordance with the persistent antiferromagnetism reported previously. Our study highlights the crucial role of lattice and orbital anisotropy for stabilizing the quasi-two-dimensional magnetism and tailoring vdW magnets.
Authors
- Thorsten Schmitt (ORCID: https://orcid.org/0000-0002-5737-1094)
- Vladimir N. Strocov (ORCID: https://orcid.org/0000-0002-1147-8486)
- Mario Di Luca
- Eugenio Paris (ORCID: https://orcid.org/0000-0002-3418-8828)
- Wei Yuan (ORCID: https://orcid.org/0000-0002-3951-1719)
- Yi Tseng (ORCID: https://orcid.org/0000-0001-6788-4398)
- Hebatalla Elnaggar (ORCID: https://orcid.org/0000-0002-4223-4054)
- Luc Testa (ORCID: https://orcid.org/0000-0002-6610-9282)
- Frank M. F. de Groot (ORCID: https://orcid.org/0000-0002-1340-2186)
- Virgile Favre (ORCID: https://orcid.org/0000-0002-3889-7787)
- Andrew Wildes (ORCID: https://orcid.org/0000-0003-3957-2818)
- Mitali Banerjee (ORCID: https://orcid.org/0009-0009-5690-5822)
- H. M. Rønnow (ORCID: https://orcid.org/0000-0002-8832-8865)
- Teguh Citra Asmara (ORCID: https://orcid.org/0000-0002-1359-734X)
- Gabriele Domaine (ORCID: https://orcid.org/0000-0002-8121-3547)
- Wenliang Zhang (ORCID: https://orcid.org/0000-0003-3278-4076)
Institutions
- Centre National de la Recherche Scientifique (FR)
- Utrecht University (NL)
- Deutsches Elektronen-Synchrotron DESY (DE)
- Paul Scherrer Institute (CH)
- Sorbonne Université (FR)
- Institut Laue-Langevin (FR)
- Institut de minéralogie, de physique des matériaux et de cosmochimie (FR)
- École Polytechnique Fédérale de Lausanne (CH)
Publication Details
- Journal
- npj Quantum Materials
- Published
- 2025-06-17
- DOI
- https://doi.org/10.1038/s41535-025-00777-0
- Citations
- 1
- Primary Topic
- 2D Materials and Applications
- Type
- article
- Field-Weighted Citation Impact
- 0.52
Funders
- National Science Foundation
- European Commission
- Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
- Nederlandse Organisatie voor Wetenschappelijk Onderzoek
- Paul Scherrer Institut
- QuantERA