Abstract:
In the framework of the London theory, the free energy of a system consisting of two concentric uniformly magnetized spheres and a spherical superconducting shell coating them in an external magnetic field parallel to the magnetization of the outer sphere is determined for an arbitrary angle between the vectors of magnetic moments of the spheres. The field of switching from the magnetization of the inner sphere antiparallel to the magnetic moment of the outer sphere to the parallel magnetization is calculated, and the condition in which such a switching does not induce the transition of the shell to the normal state are determined.