Kim-Type Critical State Models and Critical Currents on Thallium Based Superconductors
Sprache des Titels:
The two extended formulae in the power form of the Kim critical state model were used to fit the critical currents versus the dc applied magnetic field. Two samples of thallium based supercondustors: the (Tl0.6Pb0.24Bi0.16)(Sr0.9Ba0.1)2Ca2Cu3Oy film on single-crystalline lanthanum aluminate and the bulk (Tl0.5Pb0.5)Sr2(Ca1.8Gd0.2)Cu2Oy were chosen to test the models. The formulae were compared to the percolation model described by the exponential expression. The first model fits the experimental data better for the thallium based film, whereas the second approach is better for the thallium based bulk sample.