Magnetic-field dependence of the local critical current density in the second-generation HTSC tapes

Abstract

An experimental-computational algorithm of precisely determining the dependence of the local critical current density in a superconducting film on the local magnetic field is developed. The determination is performed proceeding from the dependence of the transport critical current through a wide superconducting tape on the external magnetic field. It is shown that the existing formulas approximating this dependence do not allow the solution of this problem with an accuracy provided by modern experimental techniques. To provide a necessary accuracy of the solution, a four-parametric approximation formula is proposed and the parameters of this dependence are determined by the example of the second-generation HTSC tape.