Enhanced superconductivity and mixed-dimensional behaviour in infinite-layer samarium nickelate thin films
Rare-earth infinite-layer nickelates are emerging unconventional superconductors, with materials synthesis largely limited to early lanthanide compounds. Here, we report phase-pure samarium-based nickelate thin films on (LaAlO<sub>3</sub>)<sub>0.3</sub>(Sr<sub>2</sub>TaAlO<sub>6</sub>)<sub>0.7</sub> (001) substrates, including the first demonstration of Sm<sub>1-x</sub>Sr<sub>x</sub>NiO<sub>2</sub>. Co-doped compounds achieve a record-small c-axis parameter (3.26 Å) and superconducting transitions up to 32.5 K, revealing a clear correlation between decreasing c-axis parameter and increasing critical temperature across different rare-earth systems. Angle-dependent magnetoresistance shows a hybrid 2D/3D superconductivity with enhanced rare-earth 5d-Ni 3 d orbital coupling, confirmed by resonant inelastic X-ray scattering. In addition, increasing Eu concentration drives a shift toward 3D superconductivity, and Eu-containing samples exhibit distinctive negative magnetoresistance even in the superconducting state. These findings advocate clear materials design principles for higher transition temperatures and exotic physics in infinite-layer nickelate superconductors through structural engineering of the rare-earth site.
Authors
- Q S Wang
- J. Okamoto (ORCID: https://orcid.org/0000-0003-0538-6603)
- D. J. Huang (ORCID: https://orcid.org/0000-0003-4750-8453)
- Chuanying Xi (ORCID: https://orcid.org/0000-0003-3179-7019)
- Wenjie Meng
- Hsiao-Yu Huang (ORCID: https://orcid.org/0009-0001-8891-1313)
- Guangdi Zhou (ORCID: https://orcid.org/0000-0002-9378-1699)
- Hao Wang (ORCID: https://orcid.org/0000-0001-6881-9977)
- Junping Luo
- Jiayin Tang (ORCID: https://orcid.org/0000-0002-4275-2855)
- Zhuoyu Chen (ORCID: https://orcid.org/0000-0003-0193-3534)
- Lin Shi (ORCID: https://orcid.org/0000-0001-7322-4118)
- Zhengang Dong
- Mingwei Yang
- Bohan Feng
- Qingyou Lu
- Peng Gao (ORCID: https://orcid.org/0000-0003-4859-4488)
- Aile Wang
- Ruilin Mao
- Li Pi
- Danfeng Li
- Xianfeng Wu
- Zhicheng Pei
- Haoliang Huang
- Yuetong Wu
- Wenjing Xu
- Ze Wang
Institutions
- University of Science and Technology of China (CN)
- City University of Hong Kong (HK)
- Chinese University of Hong Kong (HK)
- Chinese Academy of Sciences (CN)
- Peking University (CN)
- Southern University of Science and Technology (CN)
- National Synchrotron Radiation Research Center (TW)
- Shenzhen Bay Laboratory (CN)
- High Magnetic Field Laboratory (CN)
- Hefei National Center for Physical Sciences at Nanoscale (CN)
- City University of Hong Kong, Shenzhen Research Institute (CN)
- Collaborative Innovation Center of Quantum Matter (CN)
- Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area (CN)
Publication Details
- Journal
- Nature Communications
- Published
- 2026-02-14
- DOI
- https://doi.org/10.1038/s41467-026-69650-3
- Primary Topic
- Iron-based superconductors research
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Agence Nationale de la Recherche
- National Natural Science Foundation of China