We developed a novel non-destructive and non-contact method for the measurement of critical current density (
Jc) using a permanent magnet. A high-temperature superconductor (HTS) thin-film was fixed on the stage of the system and a small cylindrical permanent magnet (Sm
2Co
17) was set above the HTS film. The repulsive force (
Fr) and attractive force between the small magnet and HTS film were measured by a high-resolution load sensor changing the distance (
L) between the HTS film and the magnet. The maximum repulsive force (
Fm) could be estimated from an experimental result of the
Fr vs.
L curve. We investigated the relationship of
Jc to
Fm in several HTS samples. The standard
Jc of the HTS films was determined using the inductive measurement system made from THEVA GmbH. We found that the
Jc is approximately proportional to the
Fm normalized by the film thickness. This result indicates that the permanent magnet technique can easily estimate the
Jc of HTS films. We also found that the system can measure
Jc with sufficient reproducibility and in a short time. Moreover, it was checked to confirm that
Jc mapping of a YBCO thin film could be also measured.
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