Vortex matter in superconducting mesoscopic disks: structure, magnetization, and phase transitions

The dense vortex matter structure and associated magnetization are calculated for type-II superconducting mesoscopic disks. The magnetization exhibits generically first-order phase transitions as the number of vortices changes by one and presents two well-defined regimes: A nonmonotonous evolution of the magnitude of the magnetization jumps signals the presence of a vortex glass structure which is separated by a second-order phase transition at H-c2 from a condensed state of vortices (giant vortex) where the magnitude of the jumps changes monotonously. We compare our results with Hall magnetometry measurements by Geim et al. [Nature (London) 390, 259 (1997)] and claim that the magnetization exhibits clear traces of the presence of these vortex glass states.