Superconducting BaHfO3–GdBa2Cu3O7 Nanocomposite Thin Films: Influence of Growth Temperature and Deposition Rate on Transport Properties
Superconducting GdBa<sub>2</sub>Cu<sub>3</sub>O<sub>7</sub> films with 2.5 wt% of BaHfO<sub>3</sub> were deposited by pulsed laser deposition using an Nd:YAG laser (<italic>λ</italic> = 355 nm), and their structural and electrical properties were investigated in dependence of substrate temperature <italic>T</italic><sub>sub</sub> and deposition rate (i.e., laser repetition rate <italic>v</italic><sub>dep</sub>). The irreversibility lines show the strongest shift toward higher magnetic fields at intermediate <italic>T</italic><sub>sub</sub> and lower <italic>v</italic><sub>dep</sub>. The self-field <italic>J</italic><sub>c</sub> decreases by a factor of 2 compared with the pristine sample, but the situation improves in the high field region. The angular dependence of <italic>J</italic><sub>c</sub> at 1, 5, and 9 T shows a large <italic>c</italic>-axis peak at 180<sup>o</sup>, which indicates strongly correlated pinning at BHO nanocolumns.