Fabrication of BaHfO₃doped Gd₁Ba₂Cu₃O_7−δcoated conductors with the high<i>I</i>_cof 85 A/cm-w under 3 T at liquid nitrogen temperature (77 K)

Abstract

The introduction of effective artificial pinning centers into pulsed laser deposition derived Gd1Ba2Cu3O7−δ coated conductors has been studied with a view to improving the Ic–B–θ properties. BaMOx (M = metal) was introduced into Gd1Ba2Cu3O7−δ film, with the expectation of forming fine nanorods such as BaZrO3 ones. BaHfO3 doped Gd1Ba2Cu3O7−δ coated conductors showed remarkably good Ic–B–θ characteristics, even at high temperature. A short sample with 1 µm film thickness prepared using a reel-to-reel system showed a minimum Ic value of 30 A/cm-w@77 K (A/cm-w@77 K to be read as 'amps per centimeter width, at 77 K') at 3 T. The minimum Jc value of ∼0.3 MA cm−2@77 K at 3 T was independent of the film thickness up to 2.9 µm. The 2.9 µm thick film showed a minimum Ic value of 84.8 A/cm-w@77 K at 3 T, corresponding to >200 A/cm-w@65 K at 5 T.