CURRENT DISTRIBUTION IN A SUPERCONDUCTING SEGMENT OF A CYLINDRICAL WIRE

Abstract

We consider the classical formulation of the problem of the direct current in a cylindrical conductor with an embedded superconductor of finite length. We present the solution obtained without boundary current spreading. It is shown that the authors' model has a fundamentally different solution. The direct current, as was shown in the previous work of the authors, is pushed in any type of a conductor to the surface together with the magnetic field, which leads to the so-called surface current. This current can be regarded as a volume one but flowing in a thin layer of finite thickness. Because this thickness does not depend on the thickness of the material and the nature of the conductor, it can be assumed that it is on the order of the characteristic depth of penetration of the magnetic field into the superconductor according to London’s theory.