K. Kawano et al., A study of the magnetic field distribution in an Ag-sheathed Bi2223 tape using scanning Hall sensor and magneto-optical techniques, SUPERCOND S, 13(9), 2000, pp. 1373-1377
Using both magneto-optical (MO) and scanning Hall sensor techniques, magnet
ic field distributions have been observed in a superconducting Ag-sheathed
Bi2223 monofilamentary tape in the presence of an external magnetic field.
Application of the inversion scheme to the MO contrast has allowed the two-
dimensional current distribution to be determined. The Hall sensor measurem
ents indicate that the current distribution in the core depends on the appl
ied external field, and the current flows mainly at the edge of the core in
a high external field. The magnetic Line profiles across the width of the
tape have been analysed by a numerical calculation by modelling the current
loops based on the two-dimensional current distribution from the MO image.
The analysis shows that an increase in the external field limits and narro
ws the current flow region from the whole of the core to the edge.