Abstract
The enhancement of the current-carrying capabilities of cuprate materials depends highly on the knowledge of how to tweak their doping state. The recent efforts on overdoping YBa\(_2\)Cu\(_3\)O\(_{7-\delta }\) (YBCO) to push the limit of critical current density towards the depairing critical current density are also based on the study of their doping state. We present the overdoping study of Transient Liquid Assisted Grown YBCO films through various oxygenation strategies, including oxygen-ozone mixtures and Ag surface-decoration layers. We systematically analyze how the key kinetic parameters, such as temperature, dwell time, ozone concentration, and surface modification, influence the oxygen content and superconducting properties of the films. Our results provide insights into achieving the overdoped regime in TLAG YBCO and offer a comparison with films grown via the Pulsed Laser Deposition (PLD) method. This study of overdoping on the TLAG YBCO films, which compares three distinct oxygenation methods and conducts an unprecedented analysis of the ozone-assisted process, promises a substantial enhancement in REBa\(_2\)Cu\(_3\)O\(_{7-\delta }\) (REBCO, RE = rare earth elements) fabrication.
Data availability
The data that support the findings of this study will be made available at the institutional repository “digital.csic” upon reasonable request.
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Acknowledgements
All authors thank the XRD, SEM, low-temperature laboratory, and Nanoquim clean room facilities at ICMAB and the scanning transmission electron microscopy facilities at ICN2 and ALBA synchrotron. Authors acknowledge the use of instrumentation as well as the technical advice provided by the Joint Electron Microscopy Center at ALBA (JEMCA).
Funding
Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. Authors acknowledge the European Research Council for the ULTRASUPERTAPE project (ERC-2014-ADG-669504), IMPACT project (ERC-2019-PoC-8749), SMS-INKS (ERC-2022-PoC-101081998), and EU COST actions OPERA (CA20116) and SUPERQUMAP (CA-21144). Also acknowledged is the financial support from the Spanish Ministry of Science and Innovation and the European Regional Development Fund, MCIU/AEI/FEDER for SUPERENERTECH (PID2021-127297OB-C21), “Severo Ochoa” Programs for Centers of Excellence in R&D (FUNFUTURE CEX2019-000917-S and Matrans42 CEX2023-001263-S), and HTS-JOINTS (PDC2022-133208-I00), PTI+ TransEner CSIC program for Spanish NGEU (Regulation (EU) 2020/2094). We also acknowledge the funding from Grant IU16-014206 (METCAM-FIB) to ICN2 funded by the European Union through the European Regional Development Fund (ERDF), with the support of the Ministry of Research and Universities, Generalitat de Catalunya. We also thank the Catalan Government for 2021 SGR 00440. A.K, L.S, D.G, and C.T would like to acknowledge the financial support from the Spanish Ministry of Science, Innovation and Universities through the FPI grants PRE2020-091817, PRE2019-090621, PRE2018-084537, and PRE2022-102078, respectively.
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A.K., J.G., and T.P. designed the experimental study. A.K., L.S., and C.T. performed the sample preparation, and A.K. performed the superconducting characterizations and data analysis. K.G. conducted the microstructural studies. A.K. prepared the original manuscript with contributions from co-authors. All authors contributed to the scientific discussion and revision of the manuscript.
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Kethamkuzhi, A., Saltarelli, L., Gupta, K. et al. Exploring the overdoping effects in Transient Liquid Assisted Grown YBa\(_2\)Cu\(_3\)O\(_{7-\delta }\) superconducting films. Sci Rep (2026). https://doi.org/10.1038/s41598-026-41613-0
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DOI: https://doi.org/10.1038/s41598-026-41613-0
