Superconductivity and suppressed monoclinic distortion in FeTe films enabled by higher-order epitaxy
Molecular beam epitaxy enables the growth of thin film materials with novel properties and functionalities. Typically, the lattice constants of films and substrates are designed to match to minimise disorders and strains. However, significant lattice mismatches can result in higher-order epitaxy, where commensurate growth occurs with a period defined by integer multiples of the lattice constants. Despite its potential, higher-order epitaxy is rarely used to enhance material properties or induce emergent phenomena. Here, we report single-crystalline FeTe films grown via 6:5 commensurate higher-order epitaxy on CdTe(001) substrates. Scanning transmission electron microscopy reveals self-organised periodic interstitials near the interface, arising from higher-order lattice matching. Synchrotron x-ray diffraction shows that the tetragonal-to-monoclinic structural transition in bulk FeTe is strongly suppressed. Remarkably, these films exhibit substrate-selective two-dimensional superconductivity, likely due to suppressed monoclinic distortion. These findings demonstrate the potential of higher-order epitaxy as a tool to control materials and inducing emergent phenomena.
Authors
- Ryutaro Yoshimi (ORCID: https://orcid.org/0000-0001-6200-9375)
- Minoru Kawamura (ORCID: https://orcid.org/0000-0003-0104-6257)
- Ilya Belopolski (ORCID: https://orcid.org/0000-0003-1723-8675)
- T. Arima (ORCID: https://orcid.org/0000-0002-6959-0454)
- Naoya Kanazawa (ORCID: https://orcid.org/0000-0003-3270-2915)
- Takuya Nomoto (ORCID: https://orcid.org/0000-0002-4333-6773)
- Atsushi Tsukazaki (ORCID: https://orcid.org/0000-0003-0251-063X)
- M. Kawasaki (ORCID: https://orcid.org/0000-0001-6397-4812)
- Yuki Sato (ORCID: https://orcid.org/0000-0002-9209-2437)
- Shunsuke Kitou (ORCID: https://orcid.org/0000-0002-2349-140X)
- Hajime Sagayama (ORCID: https://orcid.org/0000-0003-3816-9584)
- S. Nagahama (ORCID: https://orcid.org/0009-0002-7388-003X)
- Ryotaro Arita (ORCID: https://orcid.org/0000-0001-5725-072X)
- Yoshinori Tokura (ORCID: https://orcid.org/0000-0002-2732-4983)
Institutions
- High Energy Accelerator Research Organization (JP)
- Tohoku University (JP)
- Fujikura (Japan) (JP)
- RIKEN Center for Emergent Matter Science (JP)
- Tokyo Metropolitan University (JP)
- The University of Tokyo (JP)
Publication Details
- Journal
- Nature Communications
- Published
- 2025-12-05
- DOI
- https://doi.org/10.1038/s41467-025-65902-w
- Citations
- 1
- Primary Topic
- Iron-based superconductors research
- Type
- article
- Field-Weighted Citation Impact
- 0.43
Funders
- Japan Society for the Promotion of Science
- RIKEN
- Core Research for Evolutional Science and Technology