In‐plane textured YBa₂Cu₃O_7−δ thin films and their critical current characteristics

Bi‐textured YBa2Cu3O7−δ (YBCO) thin films with different ratios of [100] to [110] grains can be grown controllably on (100) yttria‐stabilized ZrO2 (YSZ) substrates using pulsed laser deposition. It was found that the ratio of [100] to [110] grains was determined predominantly by the laser fluence. By comparing the transport and intragranular critical currents, it is shown that the 45° grain boundaries (GBs) are only correspondent to about 18x reduction in Jc across polycrystalline bi‐texture samples. A percolation simulation was carried out to find out the relationship between Jc reduction across a single GB and in a polycrystalline thin film sample with many GBs. The calculated results were compared with the experimental data. The transport critical current for different films were also studied in the presence of applied magnetic field.