Computation of critical current in artificially structurated bulk samples from Hall measurements

Abstract

High-temperature superconducting artificially structured bulk samples, such as bulks with slanted drills or welds of different pieces along the c-axis with holes drilled in different asymmetric positions, pose a challenge for the computation of critical current maps able to spot the position of inhomogeneities, as they combine a current map in every ab-plane adapted to the drill/welding structure with the dependence of this structure on the position along the c-axis. We improve and adapt our technique of Hall probe field measurement, discretization and QR inversion to this problem by measuring the magnetic field on top and bottom of the bulk sample to obtain some spatial resolution of the current. To test our technique we apply it to both simulations with asymmetrical geometry and a real artificially structured bulk samples. © 2008 IOP Publishing Ltd.