Magnetic levitation force between a superconducting bulk magnet and a permanent magnet

TL;DR

This paper models the magnetic levitation force between a superconducting bulk magnet and a permanent magnet, highlighting how superconducting parameters and geometry influence the levitation force.

Contribution

It provides a first-principles calculation of the levitation force considering superconducting parameters and geometry effects.

Findings

Remnant current density dominates the levitation force

High critical current density increases force

Larger volume and aspect ratio enhance force

Abstract

The current density in a disk-shaped superconducting bulk magnet and the magnetic levitation force exerted on the superconducting bulk magnet by a cylindrical permanent magnet are calculated from first principles. The effect of the superconducting parameters of the superconducting bulk is taken into account by assuming the voltage-current law and the material law. The magnetic levitation force is dominated by the remnant current density, which is induced by switching off the applied magnetizing field. High critical current density and flux creep exponent may increase the magnetic levitation force. Large volume and high aspect ratio of the superconducting bulk can enhance the magnetic levitation force further.