Modeling and analysis of the electromagnetic shielding behavior of superconductors, conductors and magnetic materials

The electromagnetic shielding behavior of thin superconductor films is analyzed using two rigorously-formulated models-a dipole field applied to a plane shield, and a planewave falling on a hollow spherical shield. Here, the electromagnetic response of the superconductor is expressed in terms of complex conductivity. The same models are also applied to normal conductors both ferromagnetic and non-ferromagnetic, for comparison. Computational results show unique characteristics of the superconducting shield, e.g., even a very thin superconductor film shows an important shielding, and the frequency characteristics are different from those of ordinary materials. To enable the computation of an arbitrary 3-D shape, a new impedance formulation for thin superconducting boundary is introduced. The superconducting sphere model is analyzed and verified by comparison with the exact solution