Effects of irradiation on magnetization curves in high temperature superconductors

Abstract

Irradiation of high temperature superconductors yields effects that reveal significant information concerning the pinning mechanism. After electron irradiation highly mobile defects migrate to the surface and cause a significant reduction in the irreversible magnetization and thus demonstrates the importance of surface barriers. The realization of the role of the surface barriers resolve some of the most bothering puzzles in the magnetic behavior of high temperature superconductors. Irradiation with heavy ions which produces columnar defects induces "flux-flop" in the low field limit, from a direction determined by the field towards the defect direction. This phenomenon enables an experimental evaluation of the energy of a fluxon trapped by a columnar defect. © 1993.