Unraveling the electronic structure and magnetic transition evolution across monolayer, bilayer, and multilayer ferromagnetic Fe3GeTe2
Two-dimensional (2D) van der Waals (vdW) magnets have sparked widespread attention due to their potential in spintronic applications as well as in fundamental physics. Ferromagnetic vdW compound Fe3GeTe2 (FGT) and its Ga variants have garnered significant interest due to their itinerant magnetism, correlated states, and high magnetic transition temperature. Experimental studies have demonstrated the tunability of FGT’s Curie temperature, TC, through adjustments in quintuple layer numbers (QL) and carrier concentrations, n. However, the underlying mechanism remains elusive. In this study, we employ molecular beam epitaxy (MBE) to synthesize 2D FGT films down to 1 QL with precise layer control, facilitating an exploration of the band structure and the evolution of itinerant carrier density. Angle-resolved photoemission spectroscopy (ARPES) reveals significant band structure changes at the ultra-thin limit, while first-principles calculations elucidate the band evolution from 1 QL to bulk, largely governed by interlayer coupling. Additionally, we find that n is intrinsically linked to the number of QL and temperature, with a critical value triggering the magnetic phase transition. Our findings underscore the pivotal role of band structure and itinerant electrons in governing magnetic phase transitions in such 2D vdW magnetic materials.
Authors
- Valiya M. Hamza (ORCID: https://orcid.org/0000-0001-8693-5410)
- Steef Smit (ORCID: https://orcid.org/0000-0002-6695-8575)
- David Anthony Muller (ORCID: https://orcid.org/0000-0003-4129-0473)
- Matteo Michiardi (ORCID: https://orcid.org/0000-0001-9640-5093)
- Myung Joon Han (ORCID: https://orcid.org/0000-0002-8089-7991)
- Robert J. Green (ORCID: https://orcid.org/0000-0003-1849-1576)
- Hyungki Shin (ORCID: https://orcid.org/0000-0001-8435-4479)
- Ryan Roemer (ORCID: https://orcid.org/0000-0003-0688-0267)
- J. Larkin
- Ke Zou (ORCID: https://orcid.org/0000-0002-1181-1779)
- G. Levy (ORCID: https://orcid.org/0000-0003-2980-0805)
- Tao Jian (ORCID: https://orcid.org/0000-0001-8815-380X)
- Chan-Joong Kim (ORCID: https://orcid.org/0000-0001-5349-038X)
- Simon Godin (ORCID: https://orcid.org/0000-0001-7541-8194)
- A. Damascelli (ORCID: https://orcid.org/0000-0001-9895-2226)
- Xiyue S. Zhang (ORCID: https://orcid.org/0000-0003-1103-6415)
- Zhan Zhang (ORCID: https://orcid.org/0000-0002-7618-6134)
- Chong Liu (ORCID: https://orcid.org/0000-0002-2314-8687)
- Dong‐Chan Lee (ORCID: https://orcid.org/0000-0002-3042-6411)
Institutions
- Argonne National Laboratory (US)
- Seoul National University (KR)
- University of British Columbia (CA)
- Korea Advanced Institute of Science and Technology (KR)
- Cornell University (US)
- University of Saskatchewan (CA)
- Beijing Academy of Quantum Information Sciences (CN)
Publication Details
- Journal
- npj 2D Materials and Applications
- Published
- 2024-09-30
- DOI
- https://doi.org/10.1038/s41699-024-00499-0
- Citations
- 10
- Primary Topic
- 2D Materials and Applications
- Type
- article
- Field-Weighted Citation Impact
- 1.17
Funders
- National Science Foundation
- U.S. Department of Energy
- Gordon and Betty Moore Foundation
- Canadian Institute for Advanced Research
- Canadian Light Source
- National Research Foundation
- Canada Research Chairs
- National Research Foundation of Korea
- Mitacs
- University of Tokyo
- Canada First Research Excellence Fund
- Ministry of Science and ICT, South Korea
- Ministère de la Défense Nationale
- Office of Science
- Canadian Institutes of Health Research
- Natural Sciences and Engineering Research Council of Canada
- British Columbia Knowledge Development Fund
- Division of Materials Research
- Argonne National Laboratory