Contactless characterization of melt-textured superconducting junctions using micro-Hall sensor arrays

We use spatially resolved Hall probe magnetometry and magneto-optical imagi ng to study current-carrying properties of melt-textured high-temperature s uperconducting welds at high magnetic fields. The study of the vortex dynam ics near the junction using high-resolution Hall probe magnetometry reveale d enhanced relaxation of the magnetization at the junction at high temperat ures. We attribute this behavior to an increased local concentration of def ects near the weld which, depending on the temperature range, either facili tate enhanced relaxation or strengthen the local pinning properties. (C) 20 00 Elsevier Science B.V. All rights reserved.