The effect of the geometric factor on the V-I curve of Tail film

A numerical procedure is proposed for calculating the current density j and electric field E from measurements of the electric transport inside a sample with rectangular cross section by solving the non-linear electric field diffusion equation based upon the collective creep model. It is shown that the sample geometry greatly affects E and j and thus the V-I curve. To verify our numerical prediction, the V-I curve and critical current of Tl2Ba2CaCu2O8+x films with a rectangular cross section in various magnetic fields and temperatures were measured. Comparison shows that the numerical results agree well with the experimental data. (author)