Properties of mesoscopic superconducting thin-film rings: London approach

Superconducting thin-film rings smaller than the film penetration depth (the Pearl length) are considered. The current distribution, magnetic moment, and thermodynamic potential ℱ(H, N, v) for a flat, washer-shaped annular ring in a uniform applied field H perpendicular to the film are solved analytically within the London approach for a state with winding number N and a vortex at radius v between the inner and outer radii.