Improvement of Pinning Force and Critical Current Density in Thick YBa 2 Cu 3 O 7-δ Films Grown on SrTiO 3 Substrates Decorated with LaNiO 3 Nanodots

We have investigated by DC magnetization measurements and frequency-dependent AC susceptibility the critical current density (J (c)), pinning force (F (p)) and pinning potential in thick (1.3-1.6 mu m) YBa2Cu3O7-delta (YBCO) films grown by Pulsed Laser Deposition on SrTiO3 substrates decorated with LaNiO3 nanodots deposited by a few (5-15) laser pulses, in comparison with those of a 1 mu m thick YBCO reference sample. Experiments show that the highest improvement of superconducting properties was achieved for films grown on substrates decorated with 10 laser pulses on the LaNiO3 target, which have, at 77.3 K, a J (c) of 40-125% higher than in pure YBCO in fields between 1 and 2 T, and F (p) increased by 40%. These results could be important for further improvement of current-carrying capability of coated conductors for in-field power applications.