| dc.description |
Magnetization data of Al-doped YBCO laser ablated thin films were used to calculate the critical temperature and magnetization of the sample. These were found to be greatly dependent on the dopant concentration. Magnetization curves of samples with different Al concentrations but at the same temperature exhibit similar field dependences with no anomalous behaviour detected. The critical current density J<sub>c</sub>, extracted from the width of magnetization curve, scaled as J<sub>c</sub> = J<sub>c</sub>(0)(1-T/T<sub>c</sub>)<sup>n</sup>, with n~2.3. The temperature-dependent pinning force for samples with different Al concentration scaled well as F<sub>p</sub> = F<sub>h0</sub>(T)h<sup>p</sup>(1-h)<sup>q</sup>, where h is the reduced field and p and q are parameters of the order of 0.5 and 2, respectively. This type of scaling is in good agreement with the flux line lattice shear model. F<sub>p</sub> shows a peak behaviour that scales as a power law of H<sub>max</sub> (F<sub>p</sub>∝H<sub>max</sub><sup>n</sup>). |
