Summary: IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, VOL. 19, NO. 3, JUNE 2009 3553
Detection of Current Distribution in Bulk Samples
With Artificial Defects From Inversion
of Hall Magnetic Maps
M. Carrera, X. Granados, J. Amorós, R. Maynou, T. Puig, and X. Obradors
Abstract--A two-sided inverse Biot-Savart algorithm for the
computation of critical current distributions in High Temperature
Superconductor (HTS) pellets is introduced. It is based on simul-
taneous measurement of the magnetic field on top and bottom
of the bulk sample with a double Hall probe, and the authors'
discretization and QR inversion scheme. It yields current maps
which are detailed in the ab-plane for each half of the bulk sample
along the c-axis. The computed current is a O(1/z)-weighted
average of the real current along the c-axis over each slice. This
is the best possible resolution for current maps along the c-axis,
regardless of inversion scheme.
We demonstrate the new procedure by analyzing a non-c-homo-
geneous simulation and a real HTS pellet of cylindrical geometry
with asymmetrically drilled holes on both faces.
Index Terms--Critical current maps, hall magnetometry, HTS