Transport currents and magnetic properties of textured Bi(2223) tape
A A Zhukov; W Jahn; B Runtsch; H Kupfer; Y Yamada; R Flukiger; A A Zhukov; Dept. of Phys., Moscow State Univ., Russia; W Jahn; Dept. of Phys., Moscow State Univ., Russia; B Runtsch; Dept. of Phys., Moscow State Univ., Russia; H Kupfer; Dept. of Phys., Moscow State Univ., Russia; Y Yamada; Dept. of Phys., Moscow State Univ., Russia; R Flukiger; Dept. of Phys., Moscow State Univ., Russia
Журнал:
Superconductor Science and Technology
Дата:
1992-04-01
Аннотация:
Magnetic and transport properties of textured Bi(2223) tape with high critical transport current density (j<sub>c</sub>(77 K, 0 T)=2.8*10<sup>4</sup> A cm<sup>-2</sup>) were studied. Magnetic measurements show nongranular behaviour of shielding and transport currents for the magnetic field orientation perpendicular to the tape plane B perpendicular to p at low temperatures and low fields. At high magnetic fields and temperatures, however, quite large differences were observed, which depend on magnetic field sweep rate B and voltage criteria E<sub>c</sub>. This is connected with granularity and inhomogeneity of the current flow. It was established that the magnetic field dependence of the critical current has a general scaling behaviour: j<sub>c</sub>(B, B, T)=j<sub>c</sub>(0, B, T) f(B/B<sub>0</sub>(B, T)) where the scaling function f becomes exp(-B/B<sub>0</sub>) for B/B<sub>0</sub>>or=1. The scaling parameter B<sub>0</sub> is proportional to the irreversibility field B<sub>irr</sub>. Both B<sub>0</sub> and B<sub>irr</sub> show an exponential temperature dependence.
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