Magnetic Field Expulsion from an Infinite Cylindrical Superconductor

TL;DR

This paper analyzes how magnetic fields are expelled from an infinite cylindrical superconductor using London equations, providing detailed numerical and graphical insights into the field behavior for various penetration lengths.

Contribution

It offers a detailed analytical and numerical study of magnetic field expulsion in cylindrical superconductors based on London equations, including contour plots for different penetration lengths.

Findings

Magnetic field expulsion depends on the ratio of penetration length to cylinder radius.

Numerical results illustrate the evolution of magnetic field penetration.

Contour plots visualize magnetic energy density distribution.

Abstract

The solutions of the London equations for the magnetic field expulsion from superconductors are presented in this paper for the cylindrical symmetry. The result is analyzed in detail and represented numerically for the case of a uniform external magnetic field in the transverse plane. In particular, several contour plots of the magnetic energy density are depicted for the regions inside and around the superconducting area for a wide range of penetration lengths, showing how the expulsion and penetration of the magnetic field evolve with the ratio between the penetration length and the cylinder radius.