Angular effects of transport critical currents in high-temperature superconductor tapes
Abstract:Measurements of the critical current dependence on the angular orientation of the applied magnetic field for (Bi, Pb)2Sr2Ca2Cu3O10(BSCCO-2223)/AgMg-sheathed, mono-core BSCCO-2223/Ag-sheathed and Bi2Sr2CaCu2O8 (BSCCO-2212) dip coat tapes are presented. We have demonstrated that the procedure of measurement is an important factor for the angular effect to show. For a magnetic field only applied during the measurement of [iopmath latex="$I_c(\theta)$"] Ic() [/iopmath] (during the rotation the magnetic field is set to zero) we have found a symmetric curve, while when the magnetic field is applied during the rotation the curve is asymmetric. Moreover, we found a large difference in the critical current value between the different procedures. From our measurements, we imply two conditions are necessary to have an angular effect: (1) the magnetic field must be applied during the rotation and (2) we have to start the rotation for a magnetic field parallel to the c-axis. The results are discussed in the context of the accommodation of vortices to planar defects and surface pinning.
Document Type: Miscellaneous
Affiliations: Author to whom correspondence should be addressed.
Publication date: January 1, 2001