Vortex states in mesoscopic superconductors

Mesoscopic superconducting disks are versatile systems to study different aspects of phase transitions. In such systems one finds giant to multivortex transitions and different vortex configurations for the same vorticity. The system exhibits metastable states which can lead to paramagnetic response, non-quantized flux entry and even negative flux entry. Vortex-antivortices can be nucleated by positioning a ferromagnetic disk on top of a superconducting film.