In situ comparison of the critical current density in Y Ba₂ Cu₃ O₇₋δ thin films measured by the screening technique under two criteria

الأصل · EN

In this investigation we report the determination of the critical current density Jc flowing in a YBa₂Cu₃O₇₋δ superconducting thin film. Estimation of Jc was carried out by an inductive technique, the so-called screening technique, in which both the imaginary part of the fundamental harmonic of susceptibility χ''₁ and third harmonic voltage V₃ criteria were considered for the determination of the full penetration field. In order to verify the reliability of this technique under two criteria, we investigated the homogeneity of Jc via transport measurements conducted on four microbridges patterned in the same film. Based on the transport method we found that both techniques yield similar results in the determination of Jc for temperatures close to critical temperature Tc. However, at temperatures relatively far from Tc, the V₃ criterion showed a better agreement with the transport data. Furthermore, using both criteria, we propose a methodology to estimate in situ the coil factor associated with the V₃ criterion, avoiding in this way the need of implementing an additional technique.