REBCO Coated Conductors: Achievements and Challenges

T. Puig¹, X. Obradors¹, J. Gutierrez¹, E. Pach^1,5, R. Vlad¹, C. Pop¹, K. Gupta^1,2, S. Rasi¹, C. Torres¹, A. Kethamkuzhi¹, O. Mola¹, E. Ghiara¹, V. Bertini¹, M. Voulhoux¹, L. Salterilli¹, D. Garcia^1,3, S. Ricart¹, R. Yanez³, J. Farjas⁴, E. Solano⁵, L. Simonelli⁵

¹Institut de Ciència de Materials de Barcelona, ICMAB-CSIC, Campus UAB; 08193 Bellaterra, Spain

² Institut de Nanociencia i Nanotecnologia, ICN2, Campus UAB, 08193 Bellaterra, Spain

³ Departament de Química, Universitat Autonoma de Barcelona, Campus UAB, 08193 Bellaterra, Spain

⁴ GRMT, Department of Physics, University of Girona, E17071-Girona, Spain

⁵ ALBA Synchrotron, 08290 Bellaterra, Spain

Forty years after the discovery of REBa₂Cu₃O₇ (REBCO), REBCO coated conductors (CCs) have become a commercial reality enabling a range of emerging HTS applications, including compact fusion concepts, electrified aviation, high-capacity DC transmission, high-field magnets, and even HTS RF cavities [1,2]. However, their widespread deployment requires substantially higher production volumes than are achievable with current deposition techniques, despite significant ongoing expanding industrial efforts. The main limitation remains the intrinsically low growth rates of conventional fabrication methods [3]. To overcome this bottleneck, we are developing a scalable and cost-effective ultrafast growth approach, named Transient Liquid Assisted Growth (TLAG), which significantly enhances throughput [3,4]. TLAG is a non-equilibrium process in which REBCO grows from a transient liquid phase at rates exceeding 1000 nm/s, while maintaining high critical current densities [5,6]. The method relies on kinetic control of nucleation and growth under highly supersaturated conditions far from equilibrium. A central aspect of this work is the understanding of the growth mechanisms and their relationship with microstructure and superconducting properties. To this end, we combine in situ synchrotron techniques with complementary probes to correlate growth dynamics with structural evolution and functional properties [7], and we use high-throughput experimentation by developing inkjet-printed combinatorial compositional gradient films for fast process screening and data driving science [8]. In parallel, we investigate strategies to enhance vortex pinning through the introduction of artificial pinning centers and by tuning the electronic state toward the overdoped regime, where increased carrier density enhances the condensation energy and pinning effectiveness [9,10]. Advanced electron microscopy and high-field angular-dependent transport measurements are employed to link nanoscale structure with vortex dynamics in these rapidly grown materials. Overall, this work aims to establish a physically grounded understanding of ultrafast REBCO formation and its impact on vortex matter, toward the development of robust high-performance coated conductors for practical applications.

We acknowledge funding from EU-ERC_AdG-2014-669504 ULTRASUPERTAPE, EU-ERC-PoC-2020-IMPACT, EU-ERC-PoC-2022-SMS-INKS, CSIC-TRANSENER-PTI+, MICIN-SUPERENERTECH and SEVERO OCHOA MATRANS42 (CEX2023-001263-S)

[1] M. Noe et al, SUST (2026)

[2] L. Garcia-Tabares, Rivista del Nuovo Cimento (2025)

[3] T. Puig et al, Nat Phys Rev. (2024)

[4] L. Soler et al, Nature Communications (2020)

[5] S. Rasi et al, Advance Science (2022)

[6] A. Queralto et al, SUST (2023)

[7] L. Saltarelli et al, Adv. Materials (2025)

[8] E. Ghiara et al, Adv. Mat. Tech (2026)

[9] A. Stangl et al, Sci. Rep (2021)

[10] A. Kethamkuzhi et al, Sci. Rep (2026)