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

Abstract

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 YBa 2 Cu 3 O 7 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.

Critical State of YBCO Superconductors With Artificially Patterned Holes

“…This system has been already widely tested in the characterization of other sorts of YBCO samples, like bulk cylinders [11], rings [12], YBCO/Ag/YBCO welds [13], [14] and YBCO foams [7]. Fig.…”

Determination of the inter- and intra-granular critical currents in superconducting YBa2Cu3O7welds

“…The magnetic characterization of the welds was performed with an in-field Hall probe scanning system developed in our group [20,21,24]. The system consists of an AsGa Hall probe, with an active window of 0.1 × 0.1 mm 2 , attached to a raster controlled by two motors, that scans the surface of the sample at a distance of approximately 80-100 µm.…”

In-field Hall probe mapping system for characterization of YBCO welds

“…The system field noise was measured to be smaller than 4x10 -5 T (at 2x10 -3 Hz). The Hall system is located in a dewar placed between the two poles of an electromagnet, which allows applying an homogeneous magnetic field H perpendicular to the sample surface, ranging from -1 to 1 T [12]. The local magnetization is obtained by substracting the applied field from the local magnetic induction B z (x,y) measured over the surface:…”