Combinatorial and high-throughput experimentation (HTE) is achieving more relevance in material design, representing a turning point in the process of accelerated discovery, development, and optimization of materials based on data-driven approaches. The versatility of drop-on-demand inkjet printing (IJP) allows performing combinatorial studies through fabrication of compositionally graded materials with high spatial precision, here by mixing superconducting REBCO precursor solutions with different rare earth (RE) elements.
The homogeneity of combinatorial Y1–xGdxBa2Cu3O7 samples was designed with computational methods and confirmed by energy-dispersive X-ray spectroscopy (EDX) and high-resolution X-ray diffraction (XRD). We reveal the advantages of this strategy in the optimization of the epitaxial growth of high-temperature REBCO superconducting films using the novel transient liquid-assisted growth method (TLAG). Advanced characterization methods, such as in situ synchrotron growth experiments, are tailored to suit the combinatorial approach and demonstrated to be essential for HTE schemes. The experimental strategy presented is key for the attainment of large datasets for the implementation of machine learning backed material design frameworks.
Superconducting materials for emerging technologies
Combinatorial Screening of Cuprate Superconductors by Drop-On-Demand Inkjet Printing
Albert Queraltó*, Juri Banchewski, Adrià Pacheco, Kapil Gupta, Lavinia Saltarelli, Diana Garcia, Núria Alcalde, Cristian Mocuta, Susagna Ricart, Flavio Pino, Xavier Obradors, and Teresa Puig*
Inkjet printing (IJP) is a very appealing cost-effective deposition technique to achieve large-area solution-derived functional films. For many applications, it is very challenging to increase the film thickness in order to achieve competitive performance, for instance, high critical currents in superconducting films. In this paper, the preparation of superconducting YBa2Cu3O7 thick films (∼1.1 μm) using a single deposition is reported. Specific rules for ink design, deposition protocols, and pyrolysis processes are provided.
The functional properties of cuprates are strongly determined by the doping state and carrier density. We present an oxygen doping study of YBa2Cu3O7-δ (YBCO) thin films from underdoped to overdoped state, correlating the measured charge carrier density, nHnH, the hole doping, p, and the critical current density, Jc. Our results show experimental demonstration of strong increase of Jc with nH, up to Quantum Critical Point (QCP), due to an increase of the superconducting condensation energy.