Numerical Investigations on Edge Effects of Shielding Current Density in HTS Thick Film

The permanent magnet method for measuring critical current density in high-temperature superconducting (HTS) film is numerically investigated. Numerical results show that the critical current density is approximately proportional to the maximum repulsive force. Furthermore, the values of proportional constant rapidly increase as the value of HTS radius
R
approaches to value of permanent magnet radius
r
_m
. When the area where value of the shielding current density does not exceed the critical current density
J
_c
exists even a little it is possible to evaluate the value of critical current density by using same proportional constant only measuring the electromagnetic interaction.