Negative magnetic relaxation in superconductors

摘要

It was observed that the trapped magnetic moment of HTS tablets or annuli increases in time(negative relaxation) if they are not completely magnetized by a pulsed magnetic field. It is shown, in the framework of the Bean critical-state model, that the radial temperature gradient appearing in tablets or annuli during a pulsed field magnetization can explain the negative magnetic relaxation in the superconductor.