Proposal: a contactless microwave method to assess the critical current of superconducting films

Accurate measurement methods for the reliable characterization of the electrical transport properties of high-temperature superconducting materials are essential for the assessment of their performances and suitability for power applications. In this study, we correlate measurements of critical current J
c
in a dc external magnetic field with microwave contactless measurements of the so-called pinning constant k
p
. While J
c
requires patterning of the samples and/or high probe currents, microwave measurements can be performed in as-grown films or tapes, and thus are ideal for evaluating the performances without any further process. The parametric analysis of the correlation between J
c
and k
p
shows a clear correlation, and opens up the possibility of reliably using contactless k
p
measurements for the evaluation of J
c
in pristine samples of technological superconductors.