The Interaction Force Between a Permanent Magnet and a Superconducting Ring

The interaction force between a small magnet and a superconducting ring in assumptions of the Meissner state was analyzed using the dipole-dipole interaction model. Two configurations were evaluated: the vertical configuration when the magnetic moment lies parallel to the symmetry axis of the ring and the horizontal when it is perpendicular. The levitation force on the magnet increases by decreasing the distance from the center of the ring up to a maximum value and then decreases down to zero when the magnet is exactly at the center of the ring. The levitation force when the magnet is in the horizontal configuration is mostly higher than that when it is in the vertical configuration. Simulation results were compared with experimental results reported in literature.