Field penetration into type I superconducting cylinders

Abstract

The authors have observed the pattern of magnetic field penetration on the top surface of short cylinders of indium and tin when the field is applied parallel to the cylinder axis. They have then computed numerically the normal superconducting state phase boundary, the variation of the average field distribution in the cylinder and the field distribution outside it. Together with the experimental results the computations explain the coarse structure of the field penetration. They also show that the fine intermediate state structure in the penetration annulus can be described by Landau's unbranched model of the intermediate state, suitably modified. Finally, the magnetic moment and the average magnetic induction in the cylinders have been derived.