Enhanced ferromagnetism in monolayer Cr<sub>2</sub>Te<sub>3</sub> via topological insulator coupling
Exchange-coupled interfaces are pivotal in exploiting two-dimensional (2D) ferromagnetism. Due to the extraordinary correlations among charge, spin, orbital and lattice degrees of freedom, layered magnetic transition metal chalcogenides (TMCs) bode well for exotic topological phenomena. Here we report the realization of wafer-scale Cr<sub>2</sub>Te<sub>3</sub>down to monolayer (ML) on insulating SrTiO<sub>3</sub>(111) and/or Al<sub>2</sub>O<sub>3</sub>(001) substrates using molecular beam epitaxy. Robust ferromagnetism persists in the 2D limit. In particular, the Curie temperature<i>T</i><sub>C</sub>of 2 ML Cr<sub>2</sub>Te<sub>3</sub>increases from 100 K to ∼120 K when proximitized to topological insulator (TI) (Bi,Sb)<sub>2</sub>Te<sub>3</sub>, with substantially boosted magnetization as observed via polarized neutron reflectometry. Our experiments and theory strongly indicate that the Bloembergen-Rowland interaction is likely universal underlying<i>T</i><sub>C</sub>enhancement in TI-coupled magnetic heterostructures. The topological-surface-enhanced magnetism in 2D TMC enables further exchange coupling physics and quantum hybrid studies, including paving the way to realize interface-modulated topological electronics.
Authors
- David C. Bell (ORCID: https://orcid.org/0000-0002-8215-127X)
- Jagadeesh S. Moodera (ORCID: https://orcid.org/0000-0002-2480-1211)
- Frances M. Ross (ORCID: https://orcid.org/0000-0003-0838-9770)
- Jong K. Keum (ORCID: https://orcid.org/0000-0002-5529-1373)
- Alexandre C. Foucher (ORCID: https://orcid.org/0000-0001-5042-4002)
- Weida Wu (ORCID: https://orcid.org/0000-0003-1691-6091)
- Haile Ambaye (ORCID: https://orcid.org/0000-0002-8122-9952)
- Murod Mirzhalilov (ORCID: https://orcid.org/0000-0002-1879-3542)
- Austin J. Akey (ORCID: https://orcid.org/0000-0002-1249-6053)
- Wenbo Ge (ORCID: https://orcid.org/0000-0002-2057-2458)
- Yunbo Ou (ORCID: https://orcid.org/0000-0002-9350-8756)
- Mirko Rocci (ORCID: https://orcid.org/0000-0002-3907-5275)
- Hang Chi (ORCID: https://orcid.org/0000-0002-1299-1150)
- Alexander Duong (ORCID: https://orcid.org/0009-0002-4583-5346)
- Nandini Trivedi (ORCID: https://orcid.org/0000-0003-4098-1651)
- Kenneth S. Burch (ORCID: https://orcid.org/0000-0002-7541-0245)
- Valeria Lauter (ORCID: https://orcid.org/0000-0003-0989-6563)
- Dhavala Suri (ORCID: https://orcid.org/0000-0003-0085-7648)
- Mohit Randeria (ORCID: https://orcid.org/0000-0001-8566-5930)
- N. M. Nemes (ORCID: https://orcid.org/0000-0002-7856-3642)
- Yiping Wang (ORCID: https://orcid.org/0000-0001-7626-3278)
- José Luis Martínez (ORCID: https://orcid.org/0000-0001-9046-8237)
- D. Heiman (ORCID: https://orcid.org/0000-0002-3426-7171)
Institutions
- Rutgers, The State University of New Jersey (US)
- Boston College (US)
- Universidad Complutense de Madrid (ES)
- Oak Ridge National Laboratory (US)
- Northeastern University (US)
- Harvard University (US)
- University of Ottawa (CA)
- Instituto de Ciencia de Materiales de Madrid (ES)
- Plasma Technology (United States) (US)
- NanoScale Corporation (United States) (US)
- The Ohio State University (US)
- Indian Institute of Science Bangalore (IN)
- Massachusetts Institute of Technology (US)
Publication Details
- Journal
- Reports on Progress in Physics
- Published
- 2025-05-27
- DOI
- https://doi.org/10.1088/1361-6633/add9c5
- Citations
- 7
- Primary Topic
- 2D Materials and Applications
- Type
- article
- Field-Weighted Citation Impact
- 3.62
Funders
- Canada Research Chairs
- Natural Sciences and Engineering Research Council of Canada
- Office of Naval Research
- Basic Energy Sciences
- Air Force Office of Scientific Research
- Army Research Office