Unusual Ferromagnetic Band Evolution and High Curie Temperature in Monolayer 1<i>T</i>‐CrTe<sub>2</sub> on Bilayer Graphene
2D van der Waals ferromagnets hold immense promise for spintronic applications due to their controllability and versatility. Despite their significance, the realization and in-depth characterization of ferromagnetic materials in atomically thin single layers, close to the true 2D limit, has been scarce. Here, a successful synthesis of monolayer (ML) 1T-CrTe<sub>2</sub> is reported on a bilayer graphene (BLG) substrate via molecular beam epitaxy. Using angle-resolved photoemission spectroscopy and magneto-optical Kerr effect measurements, that the ferromagnetic transition is observed at the Curie temperature (T<sub>C</sub>) of 150 K in ML 1T-CrTe<sub>2</sub> on BLG, accompanied by unconventional temperature-dependent band evolutions. The spectroscopic analysis and first-principle calculations reveal that the ferromagnetism may arise from Goodenough-Kanamori super-exchange and double-exchange interactions, enhanced by the lattice distortion and the electron doping from the BLG substrate. These findings provide pivotal insight into the fundamental understanding of mechanisms governing 2D ferromagnetism and offer a pathway for engineering higher T<sub>C</sub> in 2D materials for future spintronic devices.
Authors
- Hayoon Im
- Ji Hoon Shim (ORCID: https://orcid.org/0000-0001-7357-0029)
- Heung‐Sik Kim (ORCID: https://orcid.org/0000-0003-0691-7605)
- Jing Xia (ORCID: https://orcid.org/0000-0001-6092-1344)
- Kyoungree Park
- Zhi‐Xun Shen (ORCID: https://orcid.org/0000-0002-1454-0281)
- Jun Woo Choi (ORCID: https://orcid.org/0000-0002-0418-8245)
- Hyejin Ryu (ORCID: https://orcid.org/0000-0003-3600-9755)
- Se Hee Lee
- Sung‐Kwan Mo (ORCID: https://orcid.org/0000-0003-0711-8514)
- Kyoo Kim (ORCID: https://orcid.org/0000-0002-7305-8786)
- Sungho Mun (ORCID: https://orcid.org/0000-0002-5083-5386)
- Choongyu Hwang (ORCID: https://orcid.org/0000-0003-2989-475X)
- Jinwoong Hwang (ORCID: https://orcid.org/0000-0002-9272-5257)
- Yong Zhong (ORCID: https://orcid.org/0000-0003-4242-2503)
- Camron Farhang (ORCID: https://orcid.org/0000-0003-0342-3685)
- Dongwook Kim (ORCID: https://orcid.org/0000-0002-5687-7739)
- Woojin Choi (ORCID: https://orcid.org/0000-0002-3591-8036)
- Ji‐Eun Lee (ORCID: https://orcid.org/0000-0001-5954-2638)
- Hyobeom Lee
Institutions
- Pohang University of Science and Technology (KR)
- Lawrence Berkeley National Laboratory (US)
- Korea Atomic Energy Research Institute (KR)
- Kangwon National University (KR)
- University of California, Irvine (US)
- SLAC National Accelerator Laboratory (US)
- UC Irvine Health (US)
- Pusan National University (KR)
- Korea Institute of Science and Technology (KR)
- Stanford University (US)
Publication Details
- Journal
- Small
- Published
- 2025-09-05
- DOI
- https://doi.org/10.1002/smll.202506671
- Citations
- 4
- Primary Topic
- 2D Materials and Applications
- Type
- article
- Field-Weighted Citation Impact
- 2.07
Funders
- U.S. Department of Energy
- Grains Research and Development Corporation
- National Research Foundation
- Ministry of Education
- Korea Institute of Science and Technology
- Korea Basic Science Institute
- Korea Atomic Energy Research Institute
- National Research Foundation of Korea
- Ministry of Science and ICT, South Korea
- Office of Science
- Basic Energy Sciences
- Division of Materials Sciences and Engineering