Temperature dependence of the Casimir force between a superconductor and a magnetodielectric

We investigate the dependence of the Casimir force between a superconducting plate ( niobium) and a magnetodielectric plate (yttrium iron garnet) on the temperature near the transition point within a two-fluid model. For large separations between the plates, the direction of the Casimir force changes from attractive to repulsive as the temperature decreases below the transition temperature, because of an increase in superconducting current density. We show that this increase in the repulsive contribution to the Casimir force, which depends on the magnetic permeability of the magnetodielectric plate, can be experimentally verified by measuring the force acting on the magnetodielectric plate inserted midway between a superconducting plate and a normal conducting plate.