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

We use spatially resolved Hall-probe magnetometry and magneto-optical imaging to study current-carrying properties of melt-textured high-temperature superconducting welds at high magnetic fields. Magneto-optical images show no deterioration of the current-carrying properties of the sample in the presence of the superconducting weld. The study of the vortex dynamics near the junction using high-resolution Hall-probe magnetometry revealed enhanced relaxation of the magnetization at the junction at high temperatures. We attribute this behavior to an increased local concentration of defects near the weld that, depending on the temperature range, either facilitates enhanced relaxation or strengthens the local pinning properties.