Numerical Simulation of Permanent Magnet Method for $J_{c}$-Measurement in HTS Thin Film: Influence of Hole to Proportional Relation

The permanent magnet method for measuring critical current density in high-temperature superconducting (HTS) film with a hole is numerically investigated. Numerical results show that the electromagnetic force decrease as the size of radius of a hole increase. This phenomenon is caused by the spatial distributions of shielding current density. Furthermore, the proportional relations are mightily broken if the size of radius of a hole is relatively larger than the values of permanent magnet radius or the case with J
_c
>; 1.0 MA/cm
²
. Here, J
_c
denotes the critical current density. This tendency may caused by the shape of HTS sample and the spatial distributions of the shielding current density.