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An industrial R&D programme is ongoing at SuperOx, aimed at improving 2G HTS wire performance in magnetic field. We introduce perovskite artificial pinning centres (APC) into the HTS layer matrix. In contrast to most studies described in the literature, we use the high rate production processing parameters and PLD equipment at SuperOx. This paper reports the results of Phase I of this programme. We fabricated 2G HTS wires by pulsed laser deposition of GdBCO films doped with 6%, 12% and 18% (molar) of BaSnO3 and 6% (molar) of BaZrO3, and compared their performance with an undoped reference sample. The depositions were carried out at production growth rates of 375, 560 and 750 nm min−1 by varying laser pulse frequency. BaZrO3 and BaSnO3 formed columnar semi-coherent nanoinclusions in the GdBCO film matrix. The average transverse size of the nanocolumns was about 5 nm, and their volume density correlated with the dopant concentration. All doped samples exhibited much lower angular anisotropy of in-field critical current and higher lift-factors than the undoped sample. Samples containing 6% BaSnO3 and deposited at the lower growth rates, had higher Ic than the undoped sample in the entire temperature range, in a wide range of magnetic field (B//c). The sample containing 6% BaZrO3 had higher Ic than the undoped sample at 20 and 4.2 K. These results are an encouraging start of our programme, as they show a positive impact of APC introduced into 2G HTS wires fabricated at production throughput. Phase II work will be focussed on maximising the improvements in specific temperature and field conditions, as well as on the verification of reproducibility of the improvements in production wires.

The effective preparation method of epitaxial VO2 films on the r-Al2O3 substrates based on the MOCVD technique and postdeposition annealing is described. The composition, orientation and morphology of the films obtained were investigated by Raman spectroscopy, XRD, EBSD, XPS, SEM and AFM methods. The samples obtained demonstrate high crystal quality and excellent physical properties: sharp metal-insulator (>10 4 resistance change) and intensive optical reflectivity (IR and THz regions) transitions. The model of VO2 films recrystallization based on the peritectic decomposition of intergrain vanadium oxide phases is proposed.The new effective chemical synthesis of the epitaxial VO 2 films with record electrical and optical switch properties is presented.

Accurate x-ray diffraction studies of epitaxial (001) YBa2Cu3O7 − x films with inclusions of BaZrO3, BaCeO3 and Y2O3 phases have been performed. They revealed that all these inclusions are compressed along their c-axis and expanded in the ab-plane. The tetragonal distortion observed increases in the row Y2O3–BaCeO3–BaZrO3. It is suggested that an unusually large decrease of YBCO c-axis lattice parameter during the post-deposition oxygenation step is the cause of the anisotropic strain. The experimental observations on reduced and reoxygenated samples support this suggestion. The reversible character of nano-inclusions’ strain appearing due to change of YBa2Cu3O7 − x oxygen content is demonstrated.