Ring-like vortex solutions to the Landau-Ginzburg equations in superconducting mesoscopic devices

Beyond the well-known Abrikosov and giant vortex configurations, we describe new types of solutions to the Landau-Ginzburg (LG) equations for low temperature superconductivity. These solutions correspond to ring-like current vortices surrounding one another in concentric patterns, which in addition may possibly be bound to a standard L fluxoid configuration in their center. These solutions are possible in mesoscopic devices, due to their finite spatial extent, and generalize the usual vortex configurations for large enough samples. They contribute additional states at a given applied magnetic field, whose metastability still needs to be assessed. Such configurations could add to the richness of the phase transition behavior of mesoscopic superconducting disks and annuli in external magnetic fields, in ways to be explored. The properties and characterization of these new configurations are described, both for mesoscopic disks and annuli. (C) 2000 Elsevier Science B.V. All rights reserved