title: Giant vortex states in type I superconductors simulated by Ginzburg-Landau equations.
abstract: The quantization of magnetic flux in superconductors is usually seen as vortices penetrating the sample. While vortices are unstable in bulk type I superconductors, restricting the superconductor causes a variety of vortex structures to appear. We present a systematic study of giant vortex states in type I superconductors obtained by numerically solving the Ginzburg-Landau equations. The size of the vortices is seen to increase with decreasing film thickness. In type I superconductors, giant vortices appear at intermediate thicknesses but they do not form a well-defined vortex lattice. In the thinnest type I films, singly quantized vortices seem to be stabilized by the geometry of the sample instead of an increase in the effective Ginzburg-Landau parameter.
authors.affiliation: Wihuri Physical Laboratory, Department of Physics and Astronomy, FIN-20014 University of Turku, Finland. heikki.palonen@utu.fi
authors.forename: H
authors.initials: H
authors.lastname: Palonen
authors.forename: J
authors.initials: J
authors.lastname: Jäykkä
authors.forename: P
authors.initials: P
authors.lastname: Paturi