Characterization of superconducting rings using an in-field Hall probe magnetic mapping system

A Hall probe magnetic imaging system that works in magnetic fields in the range -1 T to 1 T has been implemented, and it has been used to characterize the superconducting behavior of single domain melt textured YBa₂Cu₃O₇ rings. We show that in addition to the analysis of the evolution of the local magnetic field distribution when the external magnetic field is cycled, the hysteretic behavior of the magnetic moment can also be investigated after integration of the local magnetic field. The critical current density has been determined through the critical state model and it has been compared to that calculated by inversion of the Biot-Savart law. A remarkable agreement is achieved with both methods.